1. Introduction
2. Masteries
3. Summonerspells
4. Skills
5. Items

Hi! I made a mage Cho'gath. Cho'gath is very adaptable champion, so this time i used AP and magic penetration. WARNING: CHO'GATH ISN'T A TANK THIS WAY! HE ONLY DEALS MASSIVE DAMAGE!

Pretty basic mage masteries: 9/0/21
Just focused on mana regen and max mana + cooldown reduction.

For my summonerspells i choose:
1.Ignite
2.Clarity

Ignite is a great damage dealing spell and perfectly fit to finish someone off. With the masteries i choose, you get another 10 Ability Power bonus when Ignite is on cooldown.

Clarity is just for your mana restoreation. Cho'gath is easely out of mana, espacially in early game.

1.Rupture deals 80 / 135 / 190 / 245 / 305 (+100% of ability power) magic damage and it knocks your target airborne, which is very useful when there are more champions in one area or when chasing. I max this ability as soon as possible.
2.Feral scream silences enemies for 2 / 2.5 / 3 / 3.5 / 4 second(s) and deals 80 / 130 / 180 / 240 / 300 (+70% of ability power) magic damage. This attack is great because of it's superior silencing ability. But it is not as powerful as rupture.
3.Vorpal spikes is a toggle spell which makes your physical attacks launch spikes which deal 20 / 30 / 40 / 50 / 60 (+20% of ability power) magic damage to a line in front of you. It is a really nice speel in combination with Rylai's crystal scepter because of the slow effect. BEWARE: DO"T TURN IT ON BY A TURRET, YOU'LL HIT MINIONS OR CHAMPIONS AND THE TURRET WILL TARGET YOU!
4.Your ultimate:Feast
Deals 300 / 550 / 800 (+50% of ability power) damage to target champion, or 1000 damage to target minion (ignores resists). If the target is killed by Feast, Cho'Gath grows, gaining 90 / 120 / 150 maximum health (maximum 6 stacks). Cho'Gath loses up to 3 stacks upon death.
Feast is incredibly powerful, note that feast's effect also works when you eat minions!
5.Your passive:Carnivore:Whenever Cho'Gath kills a unit, he recovers 34 - 68 (+2.5 each level) health and 7-15.5 mana (+0.5 each level). Just kill as many Creeps as you can to get a health and mana bonus.

Start off with Doran's ring. After you have enough money, buy a sorcerer's shoes. Then buy a Rod of ages as soon as possible. Next Buy the Archangels staff and the rylai's crystal scepter and finally the Voidstaff and theRabadon's deathcap.

1.[/color]ue]Doran's ring[/color] provides longer lane duration because of health-bonus and mana regen. Eventually you should sell this item and buy Rabadon's Deathcap.
2.sorcerer shoes provide great magic penetration and fine movement speed.
3.Rod of ages gives a 700 health bonus, 80 ability power plus it gives you a bonus every minute (up to 10 min).
4.Archangels's staff gives ability power, mana and mana regen. Plus it gives ability power equal to 3% of your maximum mana.
5.Rylai's crystal scepter gives health, ability power and best of all: all your spells gain a slow effect.
6.Void staff gives an ability power bonus and 40% magic penetration.
It makes your spells hit extra hard.
7. Last but not least:Rabadon's Deathcap! It gives a 155 ability power bonus! Plus it gives another 30% of your total Ability Power extra. NOTE: This is an UNIQUE effect so it only works once!

I hope this build is useful and if there is anything wrong with it: please subscribe.
Thanks,

TheGreatW1ll