Hoo boi.
This is Lion from Dota 2. He is so ugly that he went through multiple remodels from the devs until they settled on his cat looking face that you see at the top of the linked pic, which still looks ugly. Not to mention that he has flabby man **** and it's part of his backstory to look ugly (his bio says he came out of hell "unrecognizable") and he has an ability named Finger of Death.
Here's his super incomplete profile, notable hax including his hellfire, turning people into frogs, mana drain, and his finger that does a variety of things ( ͡° ͜ʖ ͡°) Hide yo waifus from this guy lol
There's also Necrophos, at one point he used to have the name Necrophile until his designers realized it meant something else. Not as ugly as Lion, but still...