This is a remake of an arcade game by Taito, originally released in 1986. The game features twin Bubble Dragons - Bub (green with yellow spikes) and Bob (blue one). The journey goes through the cave of monsters to rescue their girlfriends; they move over a system of platforms, busting and pushing bubbles, avoiding enemies and collecting a variety of power-ups.
In this game, each player controls a dragon. Each player has to move along platforms, as well as jump from one platform to another one above, or to a side one, just as in most platform games. Each dragon can blow bubbles to trap enemies, who are defeated when the bubble is burst by the dragon’s spiny back. The bubbles also float for a time before bursting, and can be jumped on, allowing access to otherwise inaccessible areas. If a bubble containing an enemy bursts on its own, the enemy turns "angry", becoming faster than normal.
Contact with the enemy is not allowed, resulting in a loss of a life. To increase your score, pick up items: fruits, vegetables, diamonds, jewels, etc. These items or bonuses appear on stages after some events. Some of them increase speed, range of bubbles' firing, others give you a chance to get more score points or extra lives.
The goal is to defeat the Mad Sorcerer (stages 1 - 100) and then the Ghost (stages 101 - 200).