[Vlam]

Yeah, I always figured it was just because Abe was getting "better at it" in one way or another, and was able to possess more creatures as a result. Although I'm sure it was actually included in the game just to give the player the ability to do so.

You may be right:

Q: In the first two games of Oddworld, can Sligs tell if other Sligs are possessed? Any time I possess one and say hi to another, they reply, and then blow me away.

Alf: When Abe was first starting out, he didn't have good control over his powers. When he'd possess a Slig, the Slig would be all glassy eyed, and stumble around like a zombie. It wasn't very convincing. He's gotten much better lately, as you'll see.

http://oddworldlibrary.net/archives/...earalf08.shtml