On mechanics, old and new

I'm exploring some new mechanics for the game. For instance, in the video above you can see the deleter piece (the red icosahedron). I don't know yet if it will remain in the game, but it adds some interesting interactions for the puzzles.

Also I'm thinking about resuscitating an old mechanic, the cutters. Cutters work in pairs, and they allow cutting platforms below them when pushing one cutter against another. I have less confidence in this mechanic, because cutters produce less predictable movements (I removed them in the old prototype because of this).