His old rules was pretty decent, won a fair ammount of close combats with him in Fantasy. The fact that he swaps out the best stats in the enemy group for his own was pretty op in challenges. So high elves vs that guy... Yeah. xD Or a Str 10 Ogre suddenly turning into str 3, it's was fun as hell. Now he's not that much worth it as you say. :p

See, that's REALLY good in Fantasy, because a model's AP in close combat is determined by its strength x3 In 40k, he neither copies his target's weapons, armor, nor unit type, so he never gets an armor save and has no AP on his attacks. It's really just boiled down to "The Changeling always hits and wounds enemies on a 4+, and enemies always hit and wound The Changeling on a 4+" in 40k.

Yeah. xD But he didn't take their armor save, only took the stats on the stat line (except HP), so if you had a high enough strenght, it was pretty much no armor saves on the enemy. xD 4 str = -1 armor save, dunno what STR 10 gave you in negative armor save. But it was insane.

S10 meant that even 2+ armor no longer got a save x3 But daemons still have their ward saves in Fantasy, so The Changeling still usually had a save advantage.

Yupp. Which was beautiful because Tzeench in fantasy depending on model either had +4 ward or +3 ward save. :3c