This is a pyramid game that can be played while waiting in a long line, and is the Looney Labs holiday gift for 2009. It uses one Treehouse set of pyramids, and two goal cards per color, which can be borrowed from practically any deck (face cards, Uno, Fluxx, etc.).
Players are randomly dealt two goal cards, which show the colors they are trying to collect, and a mixed-color tree of pyramids. The owner of the set challenges another player, and the choose and simultaneously reveal one of their pyramids hidden in their hand -- or an empty hand. The player with the larger pyramid wins, except that an empty hand beats the large pyramid. The winner picks one of the loser's pyramids to keep, and the loser challenges someone else. If a player runs out of pyramids they take one from each other player.
Once someone has all 3 pyramids of one of colors of their goal cards, they reveal it. The person who first fulfills both goal cards wins.
This was Looney Labs' 2009 "Holiday Gift". A slightly different version became the 2011 "Holiday Gift" Pyramid Shambo.