Is this position legal?

What if #4 did not exist?

Legal. Piece on a2 can be a black Q, R or B. I show bR here.

Cool! My thinking for last move was:

^EDIT^:Can`t be bishop. The position before Ba2+ is an auto-draw, mate with one B is not possible.

Of course it can be a bishop.

Hmmm... it can be.

1.Nexf7 Qxf7 2.Nxf7# and 1...Qxh3#.

LMAO we should rank this "the funniest chess.com thread"

If the problem doesn't state that it's a Chess960 game, then it's considered from a usual chess game; if it's illegal in a chess game, even though it's legal in some Chess960 game, it's still illegal.

Stop trolling, troll, because you'r trolled!

1 Condition: White never had a piece in control of f7. Enjoy!

Looks legal; retract -1... Rb5xPd5 and now it should be easy to shuffle the pieces back to position. (No, the en passant is not forced; instead, it's the capture on d5 that is forced, either last turn or the turn before it.) One promotion is there, most likely promoting on b1 or d1, but there are spare captures to fiddle around. Blocking f7 with Black's units (on e6, f6, g6 for example) should be easy.

Here is what I guess the position would have looked a few moves before.

White had a pawn on c2, Bishop on b1.. Black's c3 pawn was on d4, Rook on b5. 

White plays Ba2+, black replies with Rd5+, white plays c4, black captures c4 en passant and hence we get the position.

looks legal

Chessgrandmaster2001: White may not play Ba2+ since it would mean White has control of f7.

in post #1492 the position is illegal since black has two light-square bishops.

if Qxh7 what if white plays Ngxh7