Step 1 Brilliant, Step 2 Blunder

I have just played a brilliant move. Unfortunately, I am about to play my only blunder of the game to follow my brilliant move. Can you figure out why rook b1 was brilliant but following it with rook d1 was a blunder? See if you can figure out the move to complete what could have been a game ending brilliant sequence.

If you found queen c6 would have completed the brilliant sequence that I didn't. Initially, this looks like a terrible move. Issue is it puts pressure on whites queen which is defenind the crucial d1 rook. If white takes the rook on b1 black gets the queen. If the queen takes the queen or makes any other move besides protecting the rook its checkmate.