I like Skarner. He's one of the few champions in the game that I feel really pulls off hybrid as well as a full ad or ap build, if not better. The main reason he pulls it off so well is his passive which allows him to spam the ever loving hell out of his spells and drastically lowers the cooldown on his ult. This is a good thing, but raises the question why not just go ad and attack speed? Very simple, he heeps ap to keep his shield up, and if he has his shield up he can attack faster, he can spam more, he can chase quicker, and take a hell of a lot of damage doing it.

The rune setup for this build is pretty damn straightforward, but if you want to know the specifics on why its that good here you go. Because this build utilizes a fair amount of attack speed, even with only a medium level of AD your going to be putting out a lot of physical damage so armor pen runes are pretty damn nice. In additional defense of that Skarner's base AD is relatively high, and you get plenty of attack speed from his build. Contrary to that defense I went attack speed quintessences, WHY? Because with the masteries for this build you end up with like 21 armor pen and that's good enough in my opinion but really you can use whatever freakin quints you want. In addition to a high base AD, skarner has abnormally high base levels for magic resist and armor. By adding a full set of armor seals and magic resist glyphs he ends up with enough defense that with his shield you can usually get by with no defensive items until late game.

I feel that an explanation of the mastery tree is pretty unnecessary as well, but if you really wanna know that too keep reading. To be honest there's quite a bit that you can personalize with this mastery tree but the key things I insist on points in are the 15 percent spell pen, the bottom skill in the offense tree, and the +6 to armor and magic resist. Other than that you can mix and match where you stick your remaining points, but I've played around with it and I feel this is the best bang for your buck.

Starting item: Use Doran's Blade, just do it. Initially you want to build up Skarner's physical damage because your going to max out his shield and q first so Doran's Blade is the way to go. Plus u get a sliver of lifesteal which can help you out early game. But if you really want you could use a Dagger and a health pot since you build Berserker Greaves next.

Berserker Greaves: Why? Because your building your AD up first. Plus attack speed cuts down on your cooldowns. Later in the game you end up with a healthy chunk of AD so it does pay off. Some will argue that for cooldown Ionian boots are better, and they are right; but you pass up the damage bonus and we're building hybrid so we want a bit of both and that's why I say Berserker.

Vampiric Sceptor: Unless you get a ton of kills right off the bat, which is actually very doable, you're not gonna have enough for both mats for the bilgewater cutlass at once. I prefer going with the sceptor first because at this point you'll already be putting out a good chunk of damage so healing takes priority as far as sustainability goes. From there pick up bilgewater when you can.

Bilgewater and Hextech Revolver: They build into Hextech Gunblade and you're building a hybrid character, 'nuff said.

Hextech Gunblade: This item is of unrivaled value for any hybrid build, you get ad and ap, and every bit of damage you deal gives you a bit of health back. Also its active ability is great as Skarner is a natural chaser and ganker so initiating a gank with this thing ensures your enemy won't get away before you rush up to them and drag em back with your ult.

Guinsoo's Rageblade: Again, a great hybrid item. Gives you AD and AP with attack speed to boot. I feel I've already adequately covered why you want all these things so I'm moving on.

Trinity Force: Once again, gives you all around stat bonus and a bit of extra move speed and a chance to slow so your now gonna be damn hard to escape and chase down. Also if your playing Skarner correctly you spam q constantly in combat and with his big base damage you make great use of Trinity's bonus damage.

Nashor's Tooth: TONS of attack speed, a bit of AP, and the highest cooldown reduction item in the game. Once you have this item in your arsenal you can do alot of damage and spam your abilities with unparalleled speed. In addition, once you've made it this far into the build if you're shield doesn't get taken out, as long as your constantly attacking its cooldown be up before the shield wears off, and i think that's really cool. I'd recommend going with stinger first because your AD is your primary source of damage when your low on mana. That and I did the math and if you're constantly attacking you will get more cooldown reduction from stinger than the Codex, yes even if your target is not a champion (if it is then it blows away the cooldown reduction from the Codex.)

Banshee's Veil: To be honest I never use this item, but I feel its one of the best options for your last item. I also would say that you can build your defensive item earlier in the game as needed or by preference as long as you have your Gunblade finished. You can swap this thing out for anything really and depending on who's doing most damage to you adjust accordingly. Personally I feel that if your taking alot of magic damage go with a Force of Nature for the speed bonus, but again its really to taste. If you're super late game and are sitting on too much money just get a Deathcap because it'll make your shield almost double in strength and will make your heal really good as well.

Start with the shield, but don't use it unless you need to. Save for his Q Skarner's abilities sap his mana really really fast. Next get your W so you can heal, and then his Q. At this point your now ready to jump all over people by rushing in with your sheild on and spamming Q to keep them slowed. From here max out his Shield because it makes it last long and boosts up his attack speed and move speed while its active making for an amazing chase/escape ability and ganking becomes a breeze. After that max out his Q because your start spamming it more and more. I'd save his heal for last because it doesn't heal for all that much until you have some AP which doesn't come till later in the build and to be honest it costs too much mana. Besides once you have your gunblade healing isn't gonna be an issue as Q will heal you well enough.

The skill sequence is really open to flexibility but just don't max out your heal early its not that good and just costs too much mana. Also because it degrades with each mark it consumes it will never heal you for more than double the base amount. Don't believe me? Explanation!:
Marks consumed | Amount healed | Total healing recieved
1 1.0 1.0
2 0.5 1.5
3 0.25 1.75
4 0.125 1.875
5 0.0625 1.9375
6 0.03125 1.96875
7 0.015625 1.984375

It goes on and you'll eventually get really close to 2 times the base amount but you can never get above it. If you know calculus then why the hell are you reading this you should already understand it!

You already know what all the summoner spells are and why they are good, so I'm just gonna say why I chose exhaust and ignite, and what spells you shouldn't use.

Exhaust: Because hes a mother f'ing ganker and slowing them down is good.
Ignite: Because hes a mother f'ing ganker and dealing them damage is good.

What spells not to use:

Rally: BECAUSE IT SUCKS!
Smite: THIS IS NOT A JUNGLE BUILD!
Fortify: You're not building a tank!
Revive: You shouldn't be dying a lot! No but this one w/ teleport CAN be devastating but I think that it's lame.

The rest of the summoner spells can work but your shield is usually sufficient as an escape tool so flash and ghost seem kinda redundant.

Skarned's ult is special, its kinda like taunt but better in that the target moves at the same speed as you and you have more position control.

Making best use of escape prevention:
Grab your target with your shield active or course, then drag them back for ONE second getting an initial cast of your Q off. Before your ult expires quickly turn the other direction and you will force the target behind you. This way the player still gets just as far as if you had kept going but now they have to run past you to escape which means they have to get hit with your slow as you follow up with subsequent Qs.

When to use his ult:
- In teamfights it can disrupt ults, drag the primary dps off your carry, and primarly screw up anyones attempt to escape. Use it on whatever seems to be most advantageous.

-Chasing: They about to make it to turret cover? DIVE DIVE DIVE pop your shield and drag them back.

-Greedy People: Did someone just turret dive you? PUNISH THE FOOL! wait till they about to leave cuz the last creeps about to die then drag them back in. Wait till they attack you then hold em in place.

Cool ways to make the best of his ult:
-Speed bonus: If you have a zilean and/or orianna have them speed boost you as or before you run in to ult someone and you can drag that SOB really far.
-Combo it: If your laning with someone who can grab or knockback, have them do their skill first then drag em back even further. If you have someone who can wall stun pull your target into position. Also you should drag them through AOE damage.