I'm looking for a "universal" opening. One example is the King's Indian, which you can play against e4, d4, and several other openings. What other openings, for Black or White, can be played versus most classical openings?
As white the task is much easier because you make the first move and dictate terms.
- g4 The Grob
- f4 Bird's
- Nf3 Reti
- b4 Sokolosky
As black you are more limited and have to play much more passively to be able to play the same moves against almost any white response.
The Hedgehog where you play to try and reach this kind of position:
[fen "2r1r1k1/1bqnbppp/pp1ppn2/8/2P1P3/8/PP3PPP/8 b - - 0 1"]
The Hippopotamus which looks like this (Don't mess with the Hippo!):
[fen "r2qk2r/1bpnnpb1/pp1pp1pp/8/8/8/8/8 b - - 0 1"]