There's only three that I've seen so far. Kove, Refugee Kamp and The Pit.

I've tried the input in a few other stages to no success. That either means there's only three or the others have specific locations/ timing or circumstances. For example I haven't tried the input while the Kroc was there in the Jungle, only before he arrived.

Hopefully there is more but the three we got are pretty sweet.

First of all, it's Sky Temple and second - there better freaking be ! I mean, people are practically begging for a "fall onto the ground" Stage Fatality, since they decides to mesh together Pit 1 & 2. Plus, you can sneak in a nice Deception easter-egg with Ermac.

You are next.

Guess it's not there.

Well I have noticed on the Kove, you need to be facing the middle of the arena for the Pit to work if you are in the corner. Maybe there may be more but have certain stipulations like stage Brutalities?