In Diabolika, you'll have to stop invading demons by using exploding monsters. Each of your monsters has a unique explosion pattern that will also explode when they are detonated. The ultimate goal is to eliminate demons, and if too many demons remain, you'll be overrun and you'll lose.
To succeed, you'll have to set up increasingly complex chains of monsters using their unique abilities. The result is a domino like explosion sequence.
Watching this chain happen is very satisfying, and setting up long sequences is very fun and strategic. Unfortunately, the game has one major shortcoming: the lack of an online leaderboard.