If you have two bubble powers like Wheel and Hammer, and you want to try to get something like Fire, you can drag one bubble on to another bubble back and forth.

If you do it enough you should start seeing different colors around the two bubbles. First you will hear a ring that will keep on getting higher the more you do it.

The first color is red and you get either fire, bomb or sleep powers.

The next color will be blue, and you can get sleep and ice.

Next you will see green, and you can get sleep, bean, and spark powers.

The fourth color is white and you can get cutter, sword, and sleep.

The fifth color is yellow and you get a choice of ninja, animal, and bubble powers.

The last color is irridescent (rainbow) and from that you can get rare powers like metal, ghost, bubble, and hammer.