Chack'n Pop
Released: 1983
Use bombs to rescue the caged hearts and escape from the maze!
I like this game but it's not an easy one to grok. The game consists of a single-screen maze viewed from the side (not top down) which contains one or more caged hearts. You must navigate the maze to free the hearts, kill or avoid monsters, and make it to the exit. The mazes are a very cramped affair and your character can only step up so high, but you can also walk on the ceiling if you can reach it. It's a little complicated and made trickier by how long it takes your bombs to explode. I died multiple times because I dropped a bomb in hopes of killing a monster on my tail but by the time it blew, the monster was out of the danger zone. Still, it seems like a game you could get good at with enough practice. I liked what I played, even if I didn't get real far. I'm just not gonna put in the necessary time to get good at it.
Interesting mechanics at work in this game.
I think this would be a rewarding game to sink into...but I'd rathe spend my time elsewhere 
The most notable thing about Chack'n Pop is that it's a Bubble Bobble prototype. They even use some of the same enemies. Chack'n also makes cameos in many other Taito games.
Hmm, that's interesting. I definitely like the mechanics of Bubble Bobble better though.