In X-Factor #212 Darwin's is forced to confront Hela's powers.As a result his own mutant abilities kicked in and he absorbed Hela's powers, at least briefly.
I find it hard to believe. Several times, when confronted with something very dangerous, Darwin's powers just teleported him away. If he could evolve into something so powerful to defeat Hela, why couldn't he do the same during World War Hulk?

Different writer maybe? 

 
Is Darwin turning into Black Alice all of a sudden? - taking Hela's look and powers? 
I think it's gone out of hand with his Evolution powers, 

Maybe cause of magical nature of threat+Hela could still find him so it would've been pointless

Also he tried to control his powers

He felt guily cause of teleporting away and leaving others

So maybe his will finally kicked in

Maybe cause of magical nature of threat+Hela could still find him so it would've been pointless

Also he tried to control his powers

He felt guily cause of teleporting away and leaving others

So maybe his will finally kicked in