In Brawl there are special items that look like white domes that activate when you pick them up, summoning a character from another game to fight for you for a short time, sort of like Pokemon.
Is there a list of these, what games they are from, and what their abilities are?
In particular, I'm interested in the background of one that shoots out a large green hand horizontally, which can push players off the level. What universe is this character from, what's his name, etc.?