I thought the mechanic was good, the physics were a little buggy sometimes where when a dead block would squash and stretch underneath the spikes, whereas they would at other times be just act as as a solid. I thought the levels were fun, and i am a sucker for central mechanics like this, the fan was a good addition.
The only other thing that might have been nice would have been if either the player was faster or if you could kill yourself on command, as the waiting to be killed would sometimes be frustrating. Other than that, great game, and i wish there were more levels to play! (0u0✿)