I played this after playing Pizza Tower which made it an interesting look back at the mechanics of that game midway through their evolution. For instance, Wario has no health bar and cannot be killed. Enemies either bonk Wario and knock him back, or else effect some sort of drastic transformation that affects how he moves. When set on fire he runs uncontrollably, when stung by a bee his face bloats up and he floats up until he hits the ceiling, etc. etc. It's a very cool idea, but in this game it means all the bosses will punish mistakes by booting you out of the arena and resetting the fight which just eats time and patience. It's a very fun idea, but this is not the perfect execution of it.

The other aspect of this I find interesting is that it's a sort of Metroidvania, but with its own weird spin on it. Each level has 4 treasures in it, usually only one is accessible at first. New treasures will either open up new levels, give Wario a powerup to access a new treasure in an old level or, most often, apply some unpredictable change to an existing level that opens up new routes. For instance a giant stone foot causes an earthquake, lowering the water level in one level, or a magic music box activates a suspension bridge. There's no real rhyme or reason, but it's fun to see the overworld and the maps themselves evolve, it feels a bit like eyemaze's GROW game where it's fun to see just how a seed or a magic trident will interact and modify the world.

Definitely worth playing if you're a Gameboy Colour fan, I love the dedicated titles for this system but I think there are only about six or seven of them around.