Introduction
Welcome to Cho'Gath
- A Sheep in Wolf's Clothing. Please try this build a few times before rating it either up or down. Cho'Gath (especially after a few 
Feasts ) is generally avoided by your opponents for by and large being a 'Tank'. This build emphasizes Ability Power with plenty of Mana Regen for spamming your abilities for minion kills, and player kills. If people catch wind of your potential 'squishiness' a bit of Tank Hybrid love is thrown in if needed. To keeping people from attacking you, while messing them up your opponents and helping your team mates is the ultimate goal of this build.
Remember to tell your team mates that you are going AP Cho/AP Cho Hybrid. You will best be served as a group by having a 'real' tank. Keep in mind that your feasts will add to the above HP total, so you will have up to 900 additional health for a 3300ish total! Also not included is the optional 
Warmog's Armor for those who like their health to be high )
This build has been tweaked quite a bit over the last few months, and hopefully it serves you well! Enjoy!
Runes
The 3x Quintessences of Fortitude are great for providing 76 extra HP right from the start. You can pick them up cheaper during certain LoL holidays if you are patient. The 9x 
Greater Mark of Magic Penetration gives great Magic Pen, which maximizes your Ability Damage output. The 9x Greater Seals of Replenishment help keep your mana full, which is helpful since you are not very useful without mana ;-). Finally, the 9x Greater Glyphs of Focus help keep your cooldowns low, allowing you to build feast stacks faster, and get in a second round of abilities on longer fights.
Masteries
For Masteries I choose a 9/0/21 with points in my chosen Summoner Spells. The Utility tree is great for providing the movement speed, Mp5, and exp bonuses, while Archaic Knowledge reenforces your Magic Pen power.
Items
The item selection is by all means flexible. I selected these items based on my own personal preferences of how I like to play Cho. The build list SHOULD be changed based upon the makeup of the opposing group. Lots of spell caster types? Build Abyssal Sceptre. People taking magic resist items? Build a 
Void Staff. Knowing how to counter your opponents builds is just as important as your own build, and is discussed below in more detail.
Anyway, I start with 
Boots of Speed and 2x 
Health Potion, 1x 
Mana Potion. The additional speed allows you to position Cho to run in for last attacks for minion gold, as well as the 
Ruptures your opponents are sure to be fleeing from. When your Rupture does hit, moving in for the follow up of 
Feral Scream and eventually Feast will keep your opponents at bay. The pots are great for extending your laning time, and for covering up any *gulp* mistakes you may make.
I almost always rush the Tear's of the Goddess and 
Archangel's Staff to start building my Mana Pool and Ability Power. The goal is to be able to use your spell A LOT to keep harassing and getting minion kills. Lots of mana and powerful spells will help you do this.
Upgraded boots only make you more lethal ;-) I like 
Mercury's Treads for the MR and CC assistance, but 
Boots of Mobility are also great fun (A Super Sized, Super Fast Cho is Awesome!) 
Sorcerer's Shoes are sweet for additional Magic Penetration. Tough choices!
Other alternate starting items I have used are 
Doran's Ring or 
Meki Pendant with 1x Health Potion and 1x Mana Potion. It really just depends on your preference.
The next item selection will be based your needs as a group and the make-up of the opposing group.
Caster Heavy? = 
Abyssal Scepter
Melee Heavy? = 
Glacial Shroud / 
Frozen Heart
Doing Fine? = 
Rylai's Crystal Scepter
Want More Health? = Warmog's Armor
You are free to be creative at this point in the build. If people are giving you a wide berth, and seldom engage you (due to your potent damage and annoying silence ability ;-) feel free to keep building massive attack power. I find that a bit of either Armor, Health, or Magic Resist helps keep me happy during more 'heated' moments.
The final items I prefer are 
Rabadon's Deathcap or 
Morello's Evil Tome for the pure AP and CDR and AP respectively. If things are going well you can focus exclusively on AP items and really become a massive damage dealing powerhouse!
Game Flow
Early Game -
Your mana will be somewhat precious early on, so I usually use Rupture to harass/farm. Keep moving and look for your moments to Rupture/ Feral Scream. You want them to respect you so that you can use your 
Vorpal Spikes to get mana-free minion kills. Don't get to fancy before level 6, but if you can hit with a Rup/FS combo you and your teammate can put a serious hurting on any opponent! His 
Carnivore ability should keep your health and mana high, but the 2x Health Potion and Mana Potion certainly help you keep your dominance over the lane. Boots of Speed help you get in/out of any situations that may arise.
Mid Game:
Once you have your Archangel's Staff you will notice that you can put quite a serious hurting on your opponents and minions alike. I 'go fishing' with my Rupture, and when it hits I quickly close the gap for a Feral Scream/ Feast if possible. Continue to farm/harass until team fights begin to break out. Continue buying items based upon your team needs and opponent team composition/build.
If opponents are really keeping their distance don't be afraid to Feast on the minions to build up your stacks. Be careful saving Feast too long, you may end up in late game with few if any stacks.
As will all phases of the game NOT DYING is crucial for not losing your Feast stacks, be somewhat aggressive, but careful.
Late Game:
You should be able to kill most opponents with your brutal Rupture/ Feral Strike/ Feast Combo. The key is to choose your spot. I begin most team fights in the middle of the pack and harass with Rupture and or Feral Scream until the battle kicks in. Remember that you are not built as a tank, but can still take a pretty good beating ). Assist in taking down the squishies while supporting your team mates. Once equipped, and even somewhat before being equipped, you can carry your team to victory.
Skill Discussion
Carnivore - Whenever Cho'Gath kills a unit, he recovers 40 - 82 (based on level) health and 8-16 mana.
Another great reason to kill minions besides their precious gold ) This ability lets you lane longer, and since you are a kick *** Cho, you will be getting lots of kills!
Rupture - Ruptures the ground at target location, popping enemy units into the air, dealing damage and slowing them.
Ruptures the ground at target location. After a short delay, enemies are launched into the air for 1 second, dealt 80/135/190/245/305 (+1) magic damage, and have their movement speed slowed by 60% for 3 seconds.
Cost 90/90/90/90/90
ManaRange 950
AHHHHHHHhhhhhhhhh, the joys of Rupture. Not only does it do great damage, it pops your victim(s) up in the air for 1 second (allowing you to close in), AND slows their movement speed. What a pain in the *** for them! There are two important parts of casting Rupture. Positioning the circle somewhat behind your target(s) is very helpful in catching them in the radius. Champs often flee to a certain side so taking that into effect can really help your hit percentage! Using Rupture on a champ, but also catching a few minions is a great way to help with your minion kill/gold totals. In any even Practice, Practice, Practice. A well placed Rupture can catch a fleeing foe, or save your Cho *** when fleeing.
Use this first when going for the kill )
An interesting side note to Rupture. I have noticed that if I am running straight towards my opponent and then cast Rupture they are much more likely to move than if I am running perpendicular (north to south if you will). Running in the same direction after casting Rupture also has less of a signaling effect than running up, casting, and retreating.
Feral Scream - Cho'Gath unleashes a terrible scream at enemies in a cone, dealing magic damage and Silencing enemies for a few seconds.
Cho'Gath screams in a cone in front of him, silencing enemies for 2/2.25/2.5/2.75/3 second(s) and causing 80/130/180/240/300 (+0.7) magic damage.
Cost 70/80/90/100/110
ManaRange 300
The Silent Killer ;-) Or should we say the silence killer? Either way, they are due for some great damage and a silence. Used as a cone it can be 'cast' outside of your initial casting radius, causing loyal Cho to run up and unload on the Ruptured opponent, and put yourself in range for a Feast! Feral Scream is also great in the beginning of team fights. Silenced opponents generally flee, or get hammered on. Their choice!
Vorpal Spikes - Cho'gath's attacks passively release deadly spikes, dealing damage to all enemy units in front of him.
Toggle: Cho'gath's physical attacks launch spikes which deal 20/30/40/50/60 (+0.2) magic damage to a line in front of him.
Cost None
Range 40
Vorpal Spikes serves two great purposes. Weakening/Killing minions, and keeping your opponents away. Sometimes, you can even accomplish both! Keeping people fearing your Rupture and Feral Scream sets you up to wack on the mobs (sending your spikes flying) which gets your gold and keeps your opponents from cashing in. Good deal!
Beware using Vorpal Spikes when taking on towers with enemies nearby as the spikes can hit the enemy and turn the tower onto you! Get used to toggling these off when tower assaults come into play with enemies, and don't forget to turn it back on!
Feast - Devours an enemy unit, dealing a high amount of damage that ignores magic resist. If the target is killed, Cho'Gath grows, gaining maximum health (maximum 6 stacks). Cho'Gath loses up to 3 stacks upon death.
Deals 300/550/800 (+0.5) true damage to target champion, or 1000 true 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.
Cost 100/100/100
ManaRange 100
Yum Yum YUM! This is what makes Cho Cho... At the end of a Rupture, Feral Scream sequence, there will be little, and probally no, life left for your victim. Unless there is a lot of teamfighting at lvl 6 I prefer to use this on minions to help build my stacks up a bit. Large Cho = INTIMIDATION! When team fights are going on I try to save this for an opponent. Try to use it as a killing blow, but using this on a squishy/wounded foe, can send them running and will give your team an advantage. Just as important to using this and getting stack is NOT DYING. Dying sucks even worse with Cho, which should make you more careful you crazy caster )
Feast has been updated on Cho'Gath so that he only loses half his stacks (rounded up) instead of 3 stacks upon death.
Summary
Enjoy the viciousness and fear that is Cho'Gath. Make your opponents respect your power, while maintaining enough presence not to lose your stacks of Feast!
Any suggestions/comments are always welcome as this build will always be a work of progress as thing keep updating.
Yum yum yum!
Build Guide
Discussion (4)
Flash - Great for escaping or the Flash/Feast treat )
Ignite - Makes you even more of a kill threat! Be sure to change masteries if using this spell.
Exhaust - Good as an escape mechanism, or for keeping yourself in range for a Feast from hell. A good viable option.
