Hi everyone,

This is my first build I post here, so go easy on me please ^^

Anyway, after some research in how Mpen and Mres reduction works I've been looking to find a good hero to get the most magic resistance reduction. My search brought me to Kayle.

I know there are also other hero's that actually have abilities to lower Mres and such, but the thing is that there are very few hero's that can carry both Abyssal Mask and Malady effectively (they're the only items in the game that can lower Mres, the rest is just Mpen). For example Fiddlesticks already has a nice passive to lower Mres on your opponents, but Malady on him is useless and with Abyssal Mask he can only get 30 Mres reduction (while Malady + Abyssal Mask can do 44 if you can get the max stacks of Malady on an opponent).

So in short, I think Kayle is the best hero (or at least one of the best) for both Malady and Abyssal Mask.

Anyway I hope you enjoy reading my guide and I'm always open for comments and suggestions.

Well there's plenty of reasons:

1) Mpen can never lower Mres below 0, Mres reduction can
2) Your whole team benefits from Mres reduction on your opponents
3) A negative Mres on you opponents makes your attacks stronger

Now to give you some math. Most hero's start out with 30 Mres and don't have it increasing naturally (trough leveling that is). This means in most cases that unless someone buys Mres items they will have 30 Mres.
Now with Abyssal Mask you have 20 Mres reduction from the go. With Malady you can get up to 24 Mres reduction if you can get the 4 stacks on your target. Together that's 44 Mres reduction, or -14 Mres on you opponent if he/she didn't buy Mres items. -14 Mres increases your magic damage by ~10%! That's a very nice bonus, especially considering your whole team can take advantage of that (as long as they do magic damage).
Now consider there are a lot of people out there that simply don't buy Mres, especially on squishy physical dps hero's Mres seems scarce. And even if they buy Mres maybe you lose out on the damage bonus of negative Mres, but then you still have good damage unless they go totally overboard on Mres (which in turn will leave them vulnerable to physical damage, or severely hurt their damage output).

Pros:

1) Good damage output
2) A pretty strong early game, especially for Kayle
3) Very strong late game, damage wise at least
4) Damage support, will allow your whole team to do more magic damage
5) Does great in caster heavy teams (or any other form of magic damage for that matter)
6) Faster then pretty much anything

Cons:

1) Gets more squishy as the game goes on, in trade for damage output
2) Needs some support late game in the form of a good tank, someone needs to keep the enemy team of your back as you heal your mates and eat faces
3) Not good in a 2v1 lane, they probably can't push you out, but you can't hold them back either
4) Meh 1v1 lane, you're better off with someone else so you can help them, you're still a support after all, but if no one else can/wants mid you can handle it most of the time
5) Snowball damage due to Malady, it takes a few attacks to max out your damage output and some hero's can escape in that time

Pretty standard runes for a caster I would say. Greater Quintessence of Health, Greater Glyph of Cooldown Reduction, Greater Glyph of Scaling Cooldown Reduction, Greater Mark of Magic Penetration and Greater Seal of Scaling Mana Regeneration.

The flat health really helps your early game, which is a weak point of Kayle normally.

The mana regen seals are really needed because Kayle is a mana hungry girl, even at level 18 you can still run into a mana shortage if you're healing and attacking a lot.

After trying this combination of Greater Glyph of Cooldown Reduction and Greater Glyph of Scaling Cooldown Reduction I've kinda fallen in love with it. Combined with the masteries and Nashor's Tooth they'll give you 40.1% CDR. While you should still care with ability spam that CDR at least makes sure your Intervention is up whenever you need it. You might also notice there are still 2 glyph slots empty, you can put anything you want in those. Anything from AS to AP per level glyphs. It'll probably matter little and it won't do much, but every bit is nice + with flat CDR glyphs only you won't get the 6% CDR you need. At the moment I run Mpen glyphs in those 2 remaining slots, but feel free to put in anything you want.

Mpen marks, also to help you early game and against the hero's that do buy Mres. 0 Mres is still better then 10 Mres on your opponent, right?

After trying out Kayle with the utility tree for quite a few games I really like it so far. The extra CDR, mana and mana regen is very nice. The extra bit of speed doesn't hurt either. Also the extra mana regen is so good that Fiendish Codex really doesn't need that high of a priority.

I used to run with the defense tree simply to get rid of Kayle's squishy-ness, but with a bit more careful play the utility tree really gives you a lot more usefulness. The main reason a defense tree could be good is if your team isn't that skilled or balanced (for example lacking a good tank).

I didn't go all the way to Presence of the Master in the utility tree as your summoner spells aren't that important anyway.

The remaining points are put in the offensive tree for the 15% Mpen and Burning Ambers. The 10AP from Burning Ambers is pretty nice early game and it's probably one of the biggest AP bonuses in any tree. For example 4% extra ability power is only 8AP when you have 200AP. So maybe Burning Embers is a flat amount and it doesn't scale, but I think it's more then enough to compete with other masteries.

After I got the tings I wanted I still had a point left which I put in more crit chance, but feel free to put it somewhere else. I think crits add nicely to Kayle's damage output, but that's just me.

I can already hear some of you asking, why Ignite? Or Ghost?

Ignite stacks nicely with Reckoning, this is pretty much the reason to take Ignite over anything else. Ghost will make you so fast no one will be able to catch you or out run you.

Ignite will help you get early kills and later on it will help you crack those tough tanks, just remember to use Reckoning first.
Ghost is unbeatable in my opinion in both offense and defense, only rivaled by Exhaust and maybe Flash.

Other good choices can be: Exhaust, Flash, Teleport, Clairvoyance, Fortify, Clarity, Cleanse, Heal and perhaps even Smite. All of those have at least something good about them, the rest should definitely be ignored as they either offer too little or you shouldn't need them in the first place (yes I'm looking at you Revive).

I'm not sure what I usually do in a game, but I just look at what I need. If I get harassed a lot I get my Divine Blessing sooner and upgrade it more often, if not I'll upgrade Reckoning first.

In general the priorities are as follows:

1) Intervention
2) Reckoning
3) Righteous Fury
4) Divine Blessing

Intervention will be your main life saver for you and your team mates, so upgrade it when you can.
Reckoning will boost your DPS and is your main harassment skill. The slow also helps you or your team mates to catch a fleeing enemy (and they will).
Righteous Fury and Divine Blessing are a bit on the same level of importance. Reckoning will make Righteous Fury hit harder, so upgrading Righteous Fury is less of a priority, even though it is your main damage dealing spell.
Divine Blessing will only need upgrades if you or you team mates are only barely surviving survivable situations. By that I mean, if you 2v2 and barely escape death you need to upgrade it, or if you get pushed out of the lane you also need to upgrade it. If you 2v5 it's expected that you die and no amount of healing can save you from that, if you face that a lot then you're doing something wrong or the rest of your team is, in that case it doesn't matter what skills you take you'll die anyway.

Kayle's passive Holy Fervor is what makes her as strong as she is. It makes hybrid, AD and AP builds viable on her, the main thing I think one build has over the other is the type of damage it does and the cost.

AD builds tend to go slower because their items cost more, but in the end they will do more damage then AP builds, at the cost of supporting power though.

AP builds are the opposite, they're easier to get going, but tend to be slightly weaker then AD builds. That is compensated though by improved support and burst damage. The main issue I have with AP on Kayle is that only 2 skills really benefit from AP, namely Reckoning and Divine Blessing. Your ult doesn't use AP at all and Righteous Fury just doesn't scale very well.

Hybrid builds, Guinsoo's Rageblade is pretty easy to get and is a nice boost to your damage, but pretty much every other hybrid item is just too expensive. Trinity Force is nice, but at ~4K gold and a passive that's pretty much useless on Kayle there are many items that are better choices then that. Hextech Gunblade is not bad either, but as you're building it the components don't give you much of anything, basically leaving a big gap in your damage growth.

Starting off

With Kayle being a hybrid character she actually has a lot of items that work well, but as this build focuses on Mres reduction. Malady and Abyssal Mask are the key items that set this build apart from others.

Normally I start off with a Doran's Ring, I think it offers a lot more then a Meki Pendant + Health Potion, but that's just me. Meki Pendant usually isn't enough to quench your mana thirst anyway so you might as well get that extra HP and AP Doran's Ring gives you. Do note, I used to run these items when I used defensive masteries, if you run the new utility tree I suggest you really won't have mana problems, if you don't spam too much, so a Doran's Ring will take care of your mana needs for quite some time and the health will help you stay alive (basically I'm saying, take the ring, not the pendant).

Boots'n'stuff

After that I work my way to Boots and a Fiendish Codex. It depends, if you have to heal a lot Fiendish Codex gets more priority. If I barely have to use heal I sometimes even get Boots of Swiftness before even thinking about Fiendish Codex. So check your situation, out of mana a lot when you need it? Prioritize Fiendish Codex. Enough mana because your opponents are tower hugging for their lives? Get Boots of Swiftness quickly.
The main reason I think you should use Boots of Swiftness is because you'll out run a lot of competition with Divine Blessing + Boots of Swiftness and you need that mobility to aid your allies wherever they are. I've saved plenty of team mates because I could reach them before my opponents could. Because you'll be so fast you're also great at hunting down that 50HP lucker that escaped the rest of your team.

Again, with the utility tree I suggest the Fiendish Codex really doesn't have that much priority. So feel free to get a Stinger after first building your boots.

If you think you need other boots, be my guest. Here's my thoughts on pretty much the whole selection.
Berserker's Greaves can be good if you need AS, this build already has a lot but it's not maxed so there is room for more AS. Mobility Boots might also be a decent choice, they'll help you get back to the front faster, escape wise they're less useful though. Of course we also have the most used boots, Mercury's Treads, I think you should only get them if your opponents are CC heavy, you're not a tank so if you get trapped you'll die anyway, you should try to stay out of range and focus on 1v1 situations or where the enemy certainly won't focus you (aka when the tank initiates properly). Ninja Tabi, honestly I don't see much use for them on Kayle, you're better off running away then hoping to dodge anything. Ionian Boots of Lucidity are pretty good as well and help you get that max CDR, but if you have the runes and masteries as shown above you will max out your CDR anyway so you're better off with a different pair of boots. If you don't have the masteries and runes shown above they can be a good choice as Nashor's Tooth + Ionian Boots of Lucidity = 40% CDR.
And last but not least Sorcerer's Shoes, tough you'll be shredding mres like crazy these can help early game and helps to get those though tanks to 0 mres.

Nashor's Tooth
After Boots and Fiendish Codex you finish your boots first and then continue with Nashor's Tooth. The reason I get Nashor's Tooth so early is because it gives you a lot of what you need now. It gives some nice AS, all important mana regen, AP and even CDR! That means you can use your abilities faster and more often and they'll hit harder. If you got the masteries and runes advised by this build then you should max out your CDR at level 18 and have between 35% and 40% CDR before level 18. That should be more then enough to use your abilities whenever you need them, assuming you don't run out of mana.

It's time to reduce their Mres, muhahahaha

From here on it's your job to check what your opponent does and adapt to that. Actually that was your job from the start...

Anyway I usually start with Abyssal Mask, after I complete my boots and Nashor's Tooth, as it gives you more then Malady does, but if you're on a roll you might as well get Malady first as it's cheap and will boost your damage output nicely. Pretty much, if you tend to die due to magic damage (or simply have to recall a lot), take Abyssal Mask first and start with a Negatron Cloak. If not you can start with a Blasting Wand or get a few Daggers to make Malady.

As you complete these items you should start seeing your damage increase quite a bit. Remember to check who has bought Mres on the enemy team and who didn't and focus on taking them down. Or if they all got some Mres already just focus the squishies first, that's always a good idea.

Finalizing the build

If you get this far you're in a pretty long game, but don't worry, there is enough room to increase your damage output even more!
Technically there is only 1 more item you can get, but you can also replace Doran's Ring for something better if you manage to fill all slots. But if you replace Doran's Ring please take something else with mana and/or mana regen, Kayle really can't do without (think Manamune, Archangel's Staff, or maybe even Deathfire Grasp).

On top I've listed Madred's Bloodrazor as the last item. It's very good and in some cases it will double your magic damage output! Just a simple calculation, assume you opponent has 2K HP, 4% of that is 80 Magic damage from Madred's Bloodrazor. Now that damage gets amplified by Reckoning and -14 Mres on your opponent. So that's first a 16% increase and then ~10%. 80 * 1.16 * 1.10 = 102 Magic Damage per hit, from Madred's Bloodrazor alone! Now if your opponent has more HP it'll hit even harder. The bit of armor and AS it gives is not bad either of course.

Now if you compare something like that to, say, Guinsoo's Rageblade you'll laugh because Guinsoo's Rageblade adds like 30 Magic damage and 35 Physical dmg at max stacks (through Righteous Fury that is). Of course it's a lot cheaper then Madred's Bloodrazor and for it's price it's not bad, but at this point in the game you want the best you can get, not the semi best. Guinsoo's Rageblade is good to get sooner, but it just doesn't fit in this build if you ask me. And if you really feel you need Guinsoo's Rageblade look at one of the other Kayle builds out there, 90% of them have Guinsoo's Rageblade and I'm trying to be original here (or at least not another copy of all the other Kayle guides).

But besides Guinsoo's Rageblade and Madred's Bloodrazor there are plenty of other good choices (yeah Guinsoo's Rageblade isn't that bad after all, but there are better items, that was my point).

Hextech Gunblade is very useful if you need more damage, Lifesteal and Spellvamp, great if you encounter a lot of hero's that out shine you in the damage department, if you can steal life from them that'll make you harder to kill as long as you attack. The amount of physical damage it gives is also one of the best for Kayle (thanks to her passive).

Wit's End, highly underrated. The AS is nice and so is the Mres and magic damage it gives. 42 Magic damage per hit is more then Sword of the Divine puts out and is also more magic damage then most AP items can give on Righteous Fury. The fact it burns mana is just a nice bonus against mana using hero's, especially hero's that naturally already have mana issues will really feel the pain with this item. Though I have to say it might be on the weak side this late in the game.

Sword of the Divine might be an option if you're up against a team with a lot of dodge. The extra attack speed can generate a lot of damage and the active is nice against Jax or similar hero's with a lot of dodge.

Will of the Ancients, a good item. Maybe not the most versatile and compared to
Hextech Gunblade a bit "meh", but the extra AP and spellvamp is nice for your allies. Combined with Abyssal Mask you'll have an aura to boost your team's AP and spellvamp and an aura to lower the enemies Mres.

Banshee's Veil is a great option against a caster heavy team, maybe even more so than Force of Nature. The spell shield is just pure awesomeness and might stop that annoying CC that's been preventing you from casting your ulti at the right moment.

Death Fire Grasp, I can see how it might not be a bad item on Kayle. You're doing tons of magic damage and if you're going the percentage damage route you might as well go the full stretch and get DFG. Besides the active you also have some AP, mana regen and CDR, all of which benefit Kayle in some way (though there are better ways to max out CDR, as mentioned in the Nashor's Tooth section).

Frozen Mallet, could be an option if you need HP, a tiny bit of attack dmg and of course that sweet slow. With that slow no one will be able to escape you and probably your whole team can catch up as well then. Too bad it's only a single target slow...

Rylai's Crystal Scepter is a good alternative to Frozen Mallet and arguably better then it as well. Rylai's Crystal Scepter will turn your Reckoning into a massive slow no one can escape from and it turns Righteous Fury into an AoE slow. I'm seriously considering on taking this item more often on Kayle as it really helps keep those fast enemies in range.

Lichbane, can be a good choice, if you can spam abilities you can probably deal quite a bit of physical damage in addition to your magic damage. Just keep an eye on the CD, it's a bit on the long side, but with the amount of damage it can do it's less of an issue. The Mres, mana and AP are nice as well as the extra move speed. You don't really need the extra move speed, but if you get Lichbane for it's passive every extra thing is a nice bonus, right? This might also be a nice item in a AD Kayle build as it turns the AP gained from AD into AD again. Because 30% of your AD is turned into AP that can be pretty powerful.

Trinity Force, is of course also nice, but you don't have so much base attack to really take advantage of it and with the 2 second CD that means it's effect will strike only a few times per fight. But besides the CD all the other stats are nice, I don't think it's a bad item at all though it might be a bit expensive and for damage output there are better alternatives.

Manamune/ Archangel's Staff, both very nice items on Kayle. Both of them will give you almost infinite mana, it just depends on what type of damage you need to determine your pick. Do they have a lot of armor? Get Archangel's Staff. They got a lot of Mres? Get Manamune. Other then damage and mana these items don't offer a lot, so get them only when you spam a lot of abilities and are surviving easily (perhaps due to your spamming). Maybe Manamune is the better choice as your AP scaling on Righteous Fury is pretty bad, physical damage on the other hand doesn't suffer because Righteous Fury just makes your range longer and doesn't reduce physical damage.

Rabadon's Deathcap, just raw AP and lots of it. Nice if you like to use Reckoning as your main damage tool. For Righteous Fury it's pretty bad, off the ~200 AP Rabadon gives Righteous Fury only gains ~60 magic damage. Sure that splashes, but on a single target Madreds would be much stronger. It does boost your Divine Blessing, so if you're healing team mates a lot it might be a good item to get.

Zeke's Harbinger could be a nice item to get if your team is physical heavy. The stats it gives you and your team mates are pretty nice and the armor reduction helps them do damage as well. You might even get a Black Cleaver as well and make a Mres/Armor reduction build. But as most of your damage comes from magic I'm not sure Armor reduction will be as successful as a Mres reduction build, not to mention if you combine both you sacrifice damage output (though the rest of your team will benefit more). I normally stick to magic damage and Mres reduction though, if your team is mostly physical it's more important that you pick up what you guys lack in the magic department then to try and boost their damage output.
I have tried physical builds in practice games though, but I either run into severe mana problems or the build is just too slow compared to AP/Hybrid.

Aegis of the Legion is a nice defense item and can make a difference in team fights as your whole team benefits from it's aura. The main issue with it though is that this build focuses more on dealing damage then support and to get it as one of your last items it's a bit useless.

Sunfire Aegis, might be a nice defense item and it complements Abyssal Mask very nicely. It gives armor, HP and 40 AoE magic damage per second. The passive from Abyssal Mask makes Sunfire Aegis more effective and the HP is also nice of course. Sadly the AoE is very small and 40 damage per second isn't much. You're never really on the forefront anyway (or you shouldn't be) so yeah, it's not bad and it might help you survive, but normally it won't see much use.

Thornmail, I've never tried Thornmail on Kayle, but I think it can be a very effective item on her if she gets focused a lot. It does magic damage and seeing how you're eating their resistance it'll be putting out a lot of damage against physicals. Honestly I don't see why some people hate so much on this item as it makes you almost invincible against physical dps hero's.

Frozen Heart, well if you got opponents who build AS this item can be a good choice thanks to it's passive. It also has mana, CD reduction and is only inferior (by 1 armor) to Thornmail in the amount of armor it gives.

Guardian Angel, a good all round defense item though the passive is usually a waste if you have to rely on it (generally when the passive activates the fight is lost anyway). But for the defensive stats it gives against a balanced team it's probably your best choice.

Warmog's Armor, I dunno, not my item of choice in the defense department. I mean you're no tank and without some Mres or Armor they'll slice through that ~1,5K hp in seconds anyway. You can take it if they do a lot of true damage or simply have a balanced mix, but generally I'd say get some armor and Mres first, after that HP if you really need it that badly.

That's pretty much every item I would even consider, the rest either offers too little or simply doesn't fit. Randuin's Omen for example is very nice, but I think it's more of a tank item, though I've listed some tank items here as well. In the end it's your decision what other items you buy. My advice is, get 1 defense item if you need it, otherwise let the tank do it's job properly and just get more AS, AP or even AD.

This is more of a tips and hints section, but maybe you'll pick up some interesting ideas.

The beginning and early game

Early game Kayle can be pretty strong, harassing your opponents with Reckoning can bring them down quite a bit if they're not careful and especially squishy hero's like Ryze really feel the pain. So harass as much as you can and if you think you can make a kill, go for it. Early on you're pretty tough as long as you don't get CCed.
You can even throw in Ignite on top of Reckoning to do some nice damage, especially combined with Righteous Fury as well you can easily get an early kill or maybe even first blood. Depending on your timing you might even be able to finish it off with a second Reckoning (the first being the initiating move).

Before you engage though, make sure you have enough mana to go in, damage and escape if you need to. I've forgotten this sometimes and against someone like Xin Zhao you'll probably pay a price for mistakes like that.

Reckoning is also a good tool to keep your opponents at distance. See them coming after you? Just blast one of them in the face and run. Early game most hero's won't be able to catch you that way and with a bit of luck it'll stay that way the whole game.

Farming with Kayle can be a royal pain in the *bleep*. Especially when the game just started (the first few waves) you usually lack the speed and strength to effectively farm. I usually use this time to just gain experience and trying to zone my opponents out of experience.

It's important to know how much damage you deal against minions so you can more effectively last hit and for Kayle last hitting minions is a must. If you just try to auto attack you'll probably make very little to no gold at all because Kayle simply doesn't have enough AS or damage to do that early game. This is one of those things you need to practice to make perfect, last hitting is good for every hero, some just need it more then others and Kayle is one of those hero's that just can't do without good last hitting.
Righteous Fury can be a useful tool in last hitting, just make sure you don't go all auto attack on those minions with Righteous Fury, usually you'll just miss last hits you could easily have had.

Use your Divine Blessing only when you really need it, early game you lack the mana regen to spam it and it can drain your mana faster then Xin Zhao can dash to you.

If you do need to run (because of a jungler gank or something) you need to check who they're focusing on. If your team mate is in trouble try to save him with your Divine Blessing. If you are in trouble use Divine Blessing on yourself. But make sure to use it on whoever has the biggest trouble but still a chance to escape. This might mean you use it on your team mate instead of yourself to make sure he can escape. Don't forget you can also use Reckoning to help by slowing an enemy, early game that alone might be enough to make them stop chasing you.

Brush is also important early game, especially in top and bottom lanes. The situation you want to create is that they know you're in there, but they don't dare to check because you pop out with Reckoning every time they get close. Try to stay as much to the edge as possible as most skill shots will be aimed right in the middle, as well as giving you a quick way to step out and harass at every opportunity.
If you manage to combine this properly with last hitting minions you'll be dominating the lane. Be careful though, you really need a team mate for this to work. Without a team mate just tower hug, your damage and harassment are nice, but they are no match in a 2 on 1 situation.

So to sum up early game, harass a lot with Reckoning. Save your Divine Blessing for when you really need it. Don't forget to last hit those minions! You can use Righteous Fury for that, just don't auto attack. Use the brush to zone your opponents out of XP and harass a lot from there. Be careful when you're alone though, you don't want to die because you weren't careful enough.

Mid game

Hopefully your items are coming along nicely at this point and you might have even had a few kills. At this point it depends on how the game is going, if your opponents are still sticking to their lanes a lot you should to. The more you can farm in lane the better.
On the other hand is your opponents are moving around a lot you should go where the most support is needed. Is their whole team mid? Go there quickly and help your team. Are there only a few mid? Then try to push a lane past the halfway mark. Pushing the minions beyond that point allows them to gradually push to the towers if they're not killed by an enemy hero. Just be careful when pushing lanes alone that you don't get ganked.

When your team is ready to roam and gank you task is to stay in the middle of the pack so you can heal everyone that might need it. If you're last you might get picked off by an attack from behind and if your first you'll most likely get focused and killed before you can even touch your ulti.
Also get your team to buy wards and stuff, you have enough money issues as it is so get someone who's less item dependent to buy wards'n'stuff. Map awareness is very important and so is the need to not have to face check the brush in which an entire team can hide.

When you do get in a team fight heal the person who gets focused by them and maybe even use your ulti on that person. I often read that the tank is the worst target to pick for you ulti, but in fact your tank might be taking so much damage because he is taunting them. In such a case it might be worthwhile to keep your tank alive a little longer so your opponents will be occupied with him until they realize they can't kill him, then they'll try to change target which usually results in a unfocused attack (pretty much everyone attacking everyone).

But in general I agree that your ulti is a waste on the tank because a good team will not focus a tank. For example a Katarina is a prime target for them, but is also a very good candidate for your ulti as she can jump in and do her ulti without taking too much damage if it's timed properly.
The main issue I have though is that Katarina tends to jump in and out of combat quickly with Shunpoo which in turn makes her hard to target. Of course you can use the portraits on the left of the screen, but that's something I forget a lot when I'm in the thick of a fight.

Late game

As you start completing your build and you're approaching end game there isn't a whole lot to add to what I told you already. Move in a group, know where your enemies are and gank and push as much as you can. Heal your mates as much as you can in between fights. Nashor's buff is very nice to have at this stage of the game so try to get it before your opponents do, that buff can be the difference between victory and defeat in many cases.
With your AS you don't have much issues pushing towers and with your heal and ulti you might even be able to tank a turret for long enough so your team can destroy it. Maybe not the most elegant way to use your abilities, but if that means you can push an inhibitor or nexus turret it might be worth it.

Throughout the game there aren't really a lot of combo's Kayle can make. Usually I go Reckoning -> Righteous Fury -> Ignite (if available and useful) -> auto attack
meanwhile I use my Divine Blessing and Intervention wherever it's needed. Sometimes you might also be able to finish it off with Reckoning, do so if you can. Reckoning can also be a tool to ensure you make a kill (aka KS), while I don't advice you do so very often it can be very nice to have a few kills to help you get the items you need. Considering Kayle can be quite hard to farm with I think it's only fair to take a few kills if you really need it.

As you're squishy your first priority is to not get gobbled up in the mayhem that some fights turn into. Try to stay at a distance and use Reckoning and Righteous Fury to attack.
Meanwhile you need to keep an eye on your team mates to see who needs your heal and who needs your ulti.

If you do find yourself in the middle of a fight don't be afraid to run out of there with Divine Blessing and maybe even Intervention if you're targeted heavily. The longer you can keep them busy with you and still escape alive the better it is (if you team is nearby and coming to rescue you that is).

Other things to watch out for are mainly CC. Pretty much every stun, knock up and silence poses a danger to you. Usually Kayle can take a few hits, but if a team has a lot of CC you have to play very carefully. Keep your distance and aid your allies who do get CCed.

Usually if someone is stunned their whole team dives on that person like it's a hamburger and they haven't eaten for days. This is a perfect target to use your ulti on as that person will probably take the biggest part of their damage output (abilities, attacks, whatever). Depending on the amount of damage that person took before you casted your ulti you might also want to throw a heal or 2 his way.
The issue is, if that happens to you, you can't do anything. Your abilities are blocked and you can't run away. Unless you have more support in your team there is little to nothing you can do. Quicksilver Sash might be an option though, as well as Cleanse of course, but in general you should be able to keep enough distance to do without those things.

Other then avoiding CC and keeping distance there isn't much you can do. Just make sure you know who you're fighting and what abilities they have. Check up regularly on the items they are carrying so you can see what type of damage they output the most and what damage they mitigate the most and make sure to take advantage of that.
You either win team fights because you support your team well with extra damage and healing, or you lose team fights because you fail at those things. Ok of course you still have to have a team that knows what it's doing, but you can't really make a guide based on a team that doesn't know what it's doing. Solo queue teams usually depend more on luck then anything else in that respect. *cough* matchmaking sucks *cough*

Well I think I've written down pretty much all I wanted to share with you, but feel free to ask questions, comment, suggest and of course vote. Also if you vote please be so kind to provide a reason for voting, especially if you vote down I really would like to know why.

I'll try to update this guide as patches are released and suggestions and comments are made.

Anyway, thanks for reading and have fun on the fields of justice ;)