hmmmm, I've never fragged a shroom, they tend to do that for themselves...prolifically. You may not be able to give your friend some immediately, but eventually you will. just put some rubble next to the shroom rock and it will eventually spread. You can hurry it up by cutting the shroom , making small lacerations to the disc, it will continue the tear all on it's own, making 2 shrooms or three, etc...