Hello there and welcome to my guide on Xerath, the Magus Ascendant! This guide flows completely from my own experiences playing him and might be flawed at some points. Don't be afraid (I know you won't) to comment to improve this guide. Without further ado, here's my guide! It's not ready, but it will get updated soon enough!

Why would you pick Xerath over other longe range casters like Lux or Ziggs? Here's my answer to that question. Xerath is very effective at both playing defensively and aggressively. He's very versatile in a way that you can bait enemies to dive you under your turret and kill them, while still keeping yourself alive with a stun and a hard slow. But you can also easily kill enemies under their turret while not even taking a risk yourself. Of course, a champion like Lux, can do same thing, can she? Yes, she can, but, unless the turret kills your enemy, you can retreat to your inner turrets and activate your ultimate, Rite of the Arcane, to finish them off. Lux AND Ziggs or even Draven can do that too. Yes, but their ultimates are far easier to evade. A timed flash can evade them all, while one flash might not save you from Xerath's three Arcane Barrage charges. On top of that, he's a bad-*** energy-wizard.

Strengths Massive range Is very riskproof Easy to wear opponents down Passive compensates mana issues a bit Decent CC Rite of the Arcane kills fleeing champs (as long as they aren't clever enough to evade)

Weaknesses Lacks escapes outside of his Shocking Orb, which has a high CD early (and Flash) If you don't watch your mana, it's gone in a second Squishy Skillshot based so requires at least some skill Low mobility

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Game decription:Every 12 seconds, Xerath's next basic attack will restore 30 / 33 / 36 / 42 / 48 / 54 / 63 / 72 / 81 / 90 / 102 / 114 / 126 / 138 / 150 / 165 / 180 / 195 (27 + 3 / 6 / 9 / 12 / 15 at each level) mana. The amount of mana restored is doubled if the attack target is a champion. This does not apply to structures.
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Explanation: This is what gives Xerath his lane-staying power. It restores mana on hit every 12 seconds and doubles on champion hits. Use this as often as possible to make sure your mana stays high enough to fend off eventual ganks or unwanted initiates. A jewel of a passive!
. Game decription:First Cast: Xerath starts charging, gradually increasing the range of Arcanopulse while decreasing his movement speed by up to 50% over the next 1.5 seconds. While charging, Xerath cannot attack or use his other abilities. After 3 seconds, Arcanopulse cancels and half the mana cost is refunded.
Second Cast: After a brief cast time, Xerath fires a beam of energy in a line that deals magic damage to all enemies hit.
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Explanation: Xerath's bread and butter. A high damage, high range, high cost spell, but low cooldown spell which you should use as effective as possible. Its high costs can mean an 'oom'-situation quickly so use it the moment the enemy champ is standing right behind or in the middle of his minions.
. Game decription:Xerath calls down a blast of arcane energy which strikes after a 0.5 second delay, dealing magic damage and slowing enemies in a target 200-radius area by 10% for 2.5 seconds. Enemies hit directly take an empowered amount of damage and are slowed by a greater amount instead. The empowered slow decays down to 10% over the duration.
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Explanation: Use this spell to set up your Shocking Orb or an Arcanopulse. Don't be too scared of using this to farm since its cooldown isn't that high, especially after some Cooldown Reduction. It can be hard to hit sometimes because it has a minor delay. Like with Shocking Orb, you have to predict the movement of your opponents to fully get the power out of this spell.
. Game decription:Xerath fires a orb of energy forward in a line that detonates on striking an enemy, dealing magic damage and stunning them for between 0.75 and 2 seconds. The stun duration increases as the orb travels.
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Explanation: Here comes Vi to gank me! Nope. Oh God, Nidalee's coming for me! Nope. A lifesaver, this spell is what makes Xerath's kit complete to **** your enemies up. Use it only when you are sure you'll hit or when you're in danger and you need to get away. Hit this, fire of Eye of Destruction and an Arcanopulse to follow and you'll see your enemy's hp disappear. This spell requires good movement prediction or a very stupid lane opponent to hit, so you'll have to train on this a little!
. Game decription:Xerath anchors himself to his current location for up to 10 seconds. While anchored, Xerath is immune to displacement effects and gains the ability to cast Arcane Barrage up to three times, but cannot cast his other abilities.

Rite of the Arcane can be cancelled early by moving or attacking and will automatically end once Arcane Barrage has been cast 3 times. If Rite of the Arcane ends without using a single cast of Arcane Barrage, the cooldown is reduced by 50%. Interrupting crowd control effects, with the exception of displacement effects, will interrupt Rite of the Arcane and put if on full cooldown.
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Explanation: I got away! I got away! Well... Pity you're playing against Xerath, cause you WILL get sniped by his almighty ultimate. If your lane opponent got away with low health, back away a bit to your turret and fire of your barrages. Try not to use it when you're standing in the middle of the lane unprotected because junglers are always where you don't want them to be. This is hard to hit though so when you notice an enemy is actively dodging you, wait a second for them to think you've disengaged on them and then surprise them with another shot.
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. Max Arcanopulse first for reasons mentioned above. It's low cooldown, high cost, high range and is, because of that, Xerath's bread and butter. Then max Eye of Destruction because of its tremendous damage when your enemy is in the center. Max Shocking Orb last, because its main use lies in its stun anyways. As with most champs, max your ultimate Rite of the Arcane as soon as you can!

I'll be completely honest, runes and masteries aren't my cup of tea, but I try to fit them into my playing style and they work fine! I'll be talking about them very shallowly

RUNES

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I'm not very good at the runes-thing, so I take these standard caster runes. Mana Regen, AP and Magic Pene are the three most important things on Xerath because they give him more damage output through either raw damage dealing (like AP and Pene) or giving more spell spammability through Mana Regen.

MASTERIES

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Standard masteries fit for Xerath's long range. He takes almost no risks and therefore can go almost full damage. Double-Edged Sword is a good mastery for him because of the range. The usual Sorcery for CDR and Expose Weakness , Mental Force and Archmage for a boost to damage. Executioner is very handy on Xerath for using his Rite of the Arcane!

START OF THE GAME These are Xerath's start items. Doran's ring for some AP and Mana Regen and 2 health potions for some sustain. You won't likely need any mana potions if you use your mana wisely. Then, like always, a warding totem. Don't return until you have at least 900 gold.

Now that you have some gold, buy a Chalice of Harmony and, if possible, Boots and Health Potions. The Chalice will not only give you a boost to mana regen (and to spammability of your spells), but will give you some Magic Resist to face those pesky AP mids.

We're slowly nearing midgame and this is the point you become stronger. Buy Haunting Guise and Sorcerer's Shoes for a lovely 30 point boost to your flat magic penetration. This, combined with Devastating Strikes , will negate half or more of your mid lane opponent's Magic Resist. The health Haunting Guise gives is a nice bonus.

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MID GAME Next, buy an Athene's Unholy Grail for some more Mana Regen, AP and a lovely 20% Cooldown Reduction. This is a must have item, together with Rabadon's Deathcap. If you have enough money, which is unlikely, buy the Deathcap first. Otherwise, get a Fiendish Codex and save up for the Grail.

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LATE GAME Next, you'll want to get more health. You're very squishy and although you can keep your distance, you're a great target and not that hard to get to. Buy Liandry's Torment first and then buy a Rylai's Crystal Scepter to top that of. With these items fully built, you'll get 600 Health points extra to make you a less desired target and give you some extra damage, in both Liandry's and Rylai's, and a slow in Rylai's.

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OPTIONAL ITEMS These are all items you can buy for that last slot, although not all of them are equally viable of course. I'll start with the item I usually pick, Void Staff. It gives even more Spell Penetration than you already have so you'll end up with a whopping 30 points flat Magic Pene and 41% Magic Pene. This will make sure you'll even be able to wreck tanks. Twin Shadows is another very viable pick, because of the Movement Speed boost, you'll gain more mobility, and its active, which is great to make sure you hit that Shocking Orb or Eye of Destruction! Rod of Ages and Lich Bane are less viable picks because of their limits. Rod of Ages needs charge time, so you'll have to fit that in somewhere, although its boosts to mana, AP and health are very welcome. Lich Bane gives a boost to Movement Speed too, but its passive is less useful than Twin Shadows' active since you should always remain at long range. Still, it can be used.

Although Xerath is quite powerful and hard to counter, he has difficulties facing some opponents. Face with caution!
. Ahri poses a threat to you. Before level 6, your range should force her to back out a bit, but it won't keep a good Ahri from farming anyways due to her occasional Spellvamping Orb of Deception. Past 6, it's you who should keep your distance. Blast her from afar and try to punish her by stunning her when she tries to Spirit Rush in and Charm you. This will be hard. Keep your Shocking Orb ready at all times. If you are able to stun her, though, you have a good chance of doing some serious damage. Stay behind your minions and wear her down.
. Akali might make you sweat. Like Ahri, you can easily face her before level 6, but take care past 6. She can Shadow Dance to you and easily take you out. A timed stun can save you once again, but it's much harder to hit compared to Ahri. You have a higher range on your Eye of Destruction and Arcanopulse than she has on her Shadow Dance. Make good use of it and don't take risks.
. Anivia should pose no threat. You outrange her by far and her low mobility might make it hard to evade you. Dominate her, but beware of her Flash Frost- Frostbite combo.
. Annie poses no threat to you personally, but her pre-6 farming is better than yours and if she manages to get to you, she'll wear you down. Wear her down and interrupt her farming and she'll be no problem late game. Her Summon: Tibbers is still annoying though as Tibbers can tank every Shocking Orb you try to throw at her. Annie should pose no threat, but don't get cocky. If she does manage to get to you, she will do some serious damage.
. Brand shouldn't be too much of a problem. Hide behind your minions to avoid his Sear, but don't hide too close to them or he might use Pillar of Flame or Conflagration to hit you anyway. Use your range!
. Like Brand, you outrange her. Still, she will and can hit you with the occasional Noxious Blast, so beware. You shouldn't be afraid of her ultimate Petrifying Gaze either, because of its low range. Deny her her farm and try to zone her.
. . Even though you outrange him hard, beware of him. He hits hard and has the perfect abilities to avoid everything you throw at him, including your only rescueing tool Shocking Orb! Approach with caution, or rather, don't approach. Wear him down from afar.
. His Barrel Roll is a pain in the ***, but otherwise, he's prone to your Arcanopulses unless he uses his Body Slam. If he tries to use that to get to you, use your Shocking Orb to keep him at a distance and fire away. Succes assured.
. No threat, at all. Katarina tries to farm? Arcanopulse and Eye of Destruction! Don't give her a chance to farm and keep her at a distance and you'll be fine. Don't take risks though, your Shocking Orb is hard to hit when she can Shunpo to you. Use your high range.
. This lovely lady isn't to be trifled with. You outrange her. Hard. But like Fizz, Leblanc doesn't care about your silly range. She'll Distortion to you and use her sigil of silence and Mimic to make short work of you. However, there's a flaw in that plan of hers. Distortion. When she jumps, use Shocking Orb to pin her down and then burst her. Against Leblanc, you should really be 'better be safe than sorry'-minded. If you deny her kills, you'll outdamage her late game anyways.
. Lux is tricky. She has some range, CC and a shield at her disposal... Not to forget that huge laser, Final Spark, which does tons of damage. But she's squishy and therefore easy to zone out. Her Lucent Singularity has slightly shorter range than your Arcanopulse, so use that well. However, be careful, because although the range is shorter, she is able to hit you with the outer range. She can throw it 1100 points away from her and it has a 350 diameter, while your Arcanopulse has a 1400 range. It's a game of zones, this one.
. He's annoying and he will push and farm hard early game. But other than that, he's merely a nuisance for you. You outrange him and can zone him, because of that. But, like Annie, he can fend off those pesky Shocking Orbs you throw at him by the cunning use of his voidling(s). Don't underestimate him and zone him out and you'll be fine.
LIST WILL BE UPDATED!