To cut a long story short, Bub is a dragon that has been turned into a human and is now out to get revenge on those responsible, whilst saving the world’s population in the process.
Bub first hops onto Insect Island, where everything seems calm and dandy. Some green worms wriggle on top of a platform just above him, but don’t seem to pose any real threat. Bub fires a rainbow, just in case. That is how he gets rid of unwanted creatures, sometimes hitting them with the edge of a rainbow and sometimes trapping them in order to earn a special item.
After a while picking up these items, Bub’s rainbow attack grows to be quite powerful. He gets to open some treasure chests full of food and jewels as well. However, danger lies at the island’s peak. A huge spider tries to have Bub as its dinner, but some well placed rainbows let him to live another day.
The following hop is on Combat Island, where military trucks and other vehicles are the order of the day. Again, at the top is a big bad boss. This time in the form of a helicopter that also shoots back projectiles at Bub. But hey, it still is no match for our hero’s rainbow power.
Next stop is Monster Island. Now here it starts getting real scary, with bats, vampires, werewolves, and Frankenstein monsters all getting ready to get a bite out of Bub. The prince of darkness himself is waiting at the top, hurling bats all over the place. But still, no match for rainbows.
Toy Island may sound tame, but the toys around the next island are quite mischievous. Water guns, springy boxing gloves, bouncy balls, you name it. To top it all off, there is a giant baby clown waiting for Bub at the top. He is somehow scarier than his previous accomplice, and so has to be taught a lesson.
Doh’s Island seems strangely familiar, but Bub cannot quite place it. There’s a strange eerie music and brick platforms everywhere. The bad guy this time around is Doh, who is quick to shoot squares directly at Bub. The rainbow kid prepares to fight back though, and Doh soon fizzes away back to the dimension from whence he came.
The next rainbow bridge takes Bub to hectic Robot Island. Worker robots move around mechanically doing their daily chores, but nuts, bolts, and spanners also come to life here. The huge robot at the end of the island is just a small nuisance before reaching the last island. Bub gives him all he’s got and the robot is quickly disposed of.
The last island is called Dragon Island, so there is no surprise that it is full of dragons and knights in shining armour as well. A huge dragon is waiting to roast Bub at the top of the last castle. The fight is tough, but in the end the dragon is defeated. Bub has managed to collect a lot of treasure. As he prepares to move it, the treasure heap starts shaking, revealing a message with a call for help beneath. The people of the Rainbow Islands are asking him to go back and save them again, and he has to make sure to collect seven big diamonds along the way or he will have to do it all over again. Sheesh!
So Bub goes back, this time with more passion, and he beats all the monsters for the second time. The people, who had been turned into bubble dragons, return to their original form again. Everyone is happy and together they celebrate their hero’s success.