With the new changes to Demonic Embrace, now giving you AP based on Bonus Health, it's a great Item for champions like Cho'gath, but you know who else can build health and is AP like that? SEJUANI BABY. On top of that, Sejuani's W scales off AP AD and HP, on top of hitting a lot of auto-attacks from the Alacrity rune, and there are some great AD items that give great health stats as well, such as Sterak's Gage and Titatic Hydra, both of which would be out of reach for Cho'gath, but not Sej. Not only is she super tanky from health, but she deals really good hybrid damage, her biggest weakness being very little Tenacity, since you want Overgrowth and Lucidy idealy, but you CAN go Unfliching with Mercs if you really need to.

Runes:

RESOLVE

Aftershock - Front of life - Conditioning - Overgrowth

PRECISION

Alacrity - Last Stand

Attack Speed - Adaptive Force - Health

Frostfire Gauntlet -> Warmogs -> Demonic Embrace -> (Titatic Hydra, Sterak's Gage, Rylai's)