Hello! I'm KillaElectriix, a (Silver 5/Bronze 1/2) Xerath main. Riot hates me and keeps demoting me to the lower divisions, and my duo partner really doesn't help. Anyway enough of that. I have a lot of experience with Xerath, and I know how to play him very well. SOOOOOOO I wanna teach people about him. Here it is!

Being really poor when it comes to IP, I use standard AP runes. 9 Magic Pen Marks, 9 Armor Seals, 9 MR Glyphs and 3 AP QUINTS. They fit almost all AP champions, regardless of play style and they help a lot. (ALL TIER 3. TIER 2 OR 1 ARE FOR POOR NOOBS)

Xerath is quite squishy, so it may be better to use 21/0/9 masteries, with 3 points in Fleet of Foot as it does help a lot. Upgrading Culinary Master helps you use your potions more efficiently, which is essential if you want to be good in LoL. (For the Offense masteries use standard AP sided masteries.)

ALL YOU NEED IS APPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP. (and some mana, movement speed, health and situational items.)

Xerath can do an extreme amount of damage if played properly and fed early/mid-game, just like most other AP champs. He has a decent amount of CC in his W (slow) and E (stun). It is essential you utilize these properly, as missing your stun can severely damage your chances of escaping from a target/focusing down a target. The main combo pre-6 would be E>W>Q, but pre-3 you may want to upgrade your Q then E, if you want a better chance of getting a kill, and it can help with escaping. However, in most situations Xerath players take W for the AoE and slow at lvl 2. First you should definitely max your Q. This is your main damage spell, apart from your ultimate. Then you should max your W, which is your main AoE and 2nd CC spell. It can help in any situation so it's definitely worth it. Next up is your E, which is the main CC spell in Xerath's toolkit. It's 1.75 sec stun (at max range) is very beneficial as it can be used for any purpose. Finally, you have your R, the Ultimate. Rite of the Arcane. It fires 3 lightning bolts from Xerath's body which damage the enemy. Remember, that when activated, press R to fire a bolt, and do not move by right-clicking or it will cancel the ult.

Passive: Mana Surge. When it is up, auto attack an enemy minion, monster or Champion to gain back Mana. Abilities: First you have your Q, Arcanopulse. This is your main damage spell, which fires a line of arcane energy from Xerath's hands. Then you have your W, Eye of Destruction. Which is your main AoE and 2nd CC spell. It fires a circle of energy onto the battlefield. Next up is your E, Shocking Orb. Which is the main CC spell. It fires a ball of energy in a straight line, stunning whatever it hits. Finally, you have your R, the Ultimate. Rite of the Arcane. It fires 3 lightning bolts from Xerath's body which damage the enemy.

In ranked you have to be cautious. Xerath is very squishy, and vulnerable to fast-moving champs like Yasuo and Ahri. Ward around the bushes and jungle entrances when you feel there is something coming on the map. Be sure to utilize your passive, properly in the early game so you don't have to waste precious gold on mana pots. (Proc-ing your passive on champions gives you the most mana, so when you can, do so.) Spend money on items that will help you in your game, such as MR if facing a strong Annie, or some armor if facing a fed Yasuo etc.

PROS

Very powerful throughout the game (if fed or played well),
Has a stable kit, including a bunch of useful CC,
Very long range, easy poke, safe laning phase.

CONS

SQUISHY af.
All skills are skillshots.
Very low mobility, virtually no escape.
Quite hard to land skills and to play but extremely fun.