This is version 0.3 of xemeraldia.

Drop the blocks.  If you drop a square on top of one of the same
color, they (as well as any neighboring blocks of the same color) will
both be shaken by an "impact".  The first impact will cause fractures;
the second will cause the block(s) to dissolve.

You can either use the arrow keys or vi-style (hjkl) keys to move/
rotate the blocks.  `s' or `p' will pause the game, and if your boss
comes along, `q' can be used to avoid an unpleasant confrontation.