Doomsday for the majority.
I'm convinced Darkseid killed him, and Doomsday revived shortly.. It's not the monster's MO to play possum, so he would have been all over Darkseid if the Omegas were completely ineffectual.
Plus, he was adapting to stuff on the fly, like Waveriders time scanning tricks, and he was already adapted against high level physical strength and energy thanks to his showdown with Superman and a Guardian/The Radiant..
Not to mention he's strong enough to break Supermans arm like it's nothing, when he's amped...
Originally posted by Warlord
Let him adapt in a playroom in order not to die from boredom in an adamantium room
Assuming she can do that before he rips her head off, or impales it with a spike... Guys pretty fast (Superman commented on his speed several times in Death of Superman), and there's no prep here.
...or that it's impossible to just adapt out of adamantium. No idea how he'd do it, but how does someone adapt against chronal energies..?
Besides Monica, is there anyone on the team who has Supermans reaction speeds?
Because, Supes couldn't avoid DD's charge on him and the rest of the JLA in Death of Superman, which he specifically stated was due to "his speed", so we can rule out the usual PIS...
Unless Sersi is a speedster herself, she may not get the chance to think before Doomsdays in the middle of the team....