It's an innovative game. Your game mechanic is great. graphics are appropriate .
But I think the collision box of spikes are frustrating, consider making their collision smaller and also try to avoid precise jumps in level design.
I suppose it would have been better to have the same button for switching king and queen
The absence of music can be felt, but overally I enjoyed it and would like to play an improved version of it in the future. Good job :)