All Ki attacks involve ki in the equation, Ki is your friend.

Ki Blast (Basic, comes to all first comers): Ki No cost

Kamehameha: attack+ki-speed 5,000 Zen

Buster Cannon: Ki-speed 2,500 Zen

Gallic Gun: Attack+ki-speed 5,000 Zen

Tri-Force Cannon: Attack+Speed 4,000 Zen

Spirit Bomb (must be level 5): Attack*Ki/Speed 20,000 Zen

More to come.