Good comments. So I suppose it would work fine if I made Life Drain save ends?
Yes, but you should decide if it's part of the hit effect, as Meepo asked, or if it's an Effect; if it's part of the hit, roll it into the hit line. If it's an Effect, then it gets its own line and happens whether the attack hits or misses a particular target.
Just remove the word 'aftereffect'.
ie. "Hit: x damage, the target loses a healing surge and takes a -3 penalty to ..."
Making itthe whole power save ends seems a little odd to me, as well as significantly more powerful than 'until the end of the Lord of Gluttony's next turn'
He looks pretty awesome, actually. Fearsome. As for balance, I'll leave it to those with more experience playing high levels to comment on the challenge level. It seems good, but I confess to have only really played up to 11th level, so I'm not sure about the difficulty.