THIS GUIDE IS HELLA OUTDATED LOL
WARNING: HUGE GUIDE TO CHOGATH
 New skill order in lane, I go QEWWWR then R>W>Q>E. I also open doran's ring instead of shield. [/edit]
 I've attached a picture of my team beating bigfatjiji's team to show that this works at high levels. I've beaten many of the top 50 with this build. This guide is due for an overhaul and I will get to it soon. In the meantime, enjoy feasting! [/edit]
 Warmog's has been removed to streamline the build! Thanks everyone! [/edit]
Added some brag pictures and a 55 minute game where I had 350 minion kills and was like 20-5. I couldn't carry vs their kogmaw, though, he was too farmed.
I've played a good bit of Cho, about 100 wins, and I used to roll a similar double snowball build.
It really does work great if you can grab a few kills early.
Honestly though I wouldn't pick up warmogs on Cho. Warmogs pretty much sucks bottom line and really Cho doesn't even need any hp from items. Buying some basic armor and magic resist along with the snowball items would probably be about the best Cho build imo. Though it has been awhile since I played him. I think I will give him a go!
Also, Warmogg's is a bad item. On anyone. For over 3K gold, you get ~1200 HP and ~90 HP regen. The regen doesn't do much for you (if you really need to regen, you can always rupture/scream a wave of minions), and for a similar price you could just stack some Giant's belts and give yourself more HP without having to stack it up, and give yourself the option to upgrade those Belts later into other beneficial items (Rylai's, Sunfire, FM, etc). The other thing of note here is that you already have a LOT of HP. Stacking items that give Armor/MR is more beneficial to your EHP than just stacking HP.
Finally, as for Scream > Vorpal at level 4, I'm not sure I can agree on this. Having one point of scream means an extra 70(+.7 AP) damage on your Rupture/Autoattack + Vorpal/Feast combo, can stop them from ruining your combo with a timely Flash/Cleanse/Heal/Ability of their own, and can stop other people's channeled ultimates from ruining your day, making it key to have at level 6. Yes, you shouldn't be spamming it at every opportunity, but "you don't have enough mana to spam it + Rupture" is not a good reason to give up the extra damage and the utility of the Silence.
You don't really have that much HP, it's the difference between 3.5k and 5k, which is HUGE when you add in things like Guardian Angel and Thornmail/Banshees. If the game isn't going late you can skip it, but I always plan for the lategame and honestly a fully farmed Warmogs on Cho makes such a big difference in teamfights. The regen is NOT trivial, because you're a siege caster with a close-range nuke. A lot of the time you don't have the luxury of farming a wave to replenish HP, and +30hp/5sec regen + bonuses for farm makes it a lot safer to be at half hp.
I'm not sure where people are getting this "Warmog's is bad (on Cho)" idea from. It's bad on other characters because they're either too slow at farming or too naturally tanky, but with Cho you really, really want survivability to preserve Feast stacks. If you don't have any hp items and you lose all your stacks on Feast you really only have about 2k hp, which isn't tanky AT ALL.
 I do agree that sometimes it's useful to have scream in mid, though, but I think the one point for 10 extra damage an attack (+30 total AoE) is pretty nice for lane control and farming. It helps to zone heroes too, you can hit them from outside of melee range for no mana. Depends on champ, against Panth/Kat/Fid you might want it to stop their Heartseeker/Death Lotus/Drain. My opponents usually aren't bad enough to die to me at level 6 anyway, though, I'm sure they're prepared to get rupture/feasted. [/edit]
AP-tank hybrid without RoA seems a little strange to me, considering it gives everything he wants.
Warmog's is pretty bad on everyone, just not as bad on cho since he farms better than average. Without any armor until very late, you might just turn into an hp-battery for a hard hitting melee with life steal like tynd or jax lol.....
Okay. So Cho' Naturally has 85 armor and 30 MR. So at 3.8K Hp, his Effective HP numbers are 7030 and 4940. If you pick up Warmogg's to take you to 5K HP, his effective HP numbers are 9250 and 6500. If, instead, you pick up Randuin's Omen and Spirit Visage (both fairly cheap and effective items that still give HP regen, the combination of the two is only a little bit more expensive than Warmogg's), your HP goes to 4.1K, your armor goes to 175, and your MR goes to 66. This makes your EHP numbers 11275 and 6683 - Higher than the Warmogg's gave you.
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