There should be an object in the room that you cast Transfiguration on, and then use Wingardium Leviosa to move it onto the chess board.
cold nebula
There should be an object in the room that you cast Transfiguration on, and then use Wingardium Leviosa to move it onto the chess board.
meager bronze
You need to transform the pot into a chess piece and then place it so that the king is in checkmate.
You can only do it if you've learned the transfiguration spell from Professor Weasley
weak shard
OMG THANK YALL SO MUCH