Needless to say, there be spoilers in here… If you have not completed Mass Effect 3 or haven't yet played the Citadel DLC than you have been warned and it's your own fault!
I've always allowed Mordin to cure the genophage, as somebody else might have gotten it wrong. During my playthroughs, I'm always left with Mordin's data pad full of fun facts and singing.
I was wondering though, in the instance that Mordin survives the mission Priority: Tuchanka, does he then later appear during the Citadel DLC like the rest of the crew?
Best Answer
No - regardless of whether Mordin survives Priority: Tuchanka or not, he will not be present during the party in the Citadel DLC. In all instances, the only Mordin content is the datapad next to the bed when you wake up the next day.
In the instance that Mordin survives, it is expected that he is in hiding, and that walking around the Citadel would expose that he is, in fact, still alive.