Zombie Zone

In Zombie Zone, you control Aya, a young girl who has lived with her father. An excellent swordsman, he has left his wife and the daughter Saki to live in a secluded place, teaching Aya sword techniques. His wife died, and Saki blamed the father for her death. She killed her own father, and went off to find an artifact to resurrect her mother. Now Aya must stop her own sister and avenge her father's death.

The gameplay is hack-and-slash with some advanced things put in. You're fighting against zombies, so your enemies are not very smart. It's basically Aya against a very large number of slowly moving enemies, a bit like in Dynasty Warriors. There is a feature called "sword fatigue": if you don't clean your sword in time, it will get stuck in an enemy, giving him an advantage over you. There are also slight RPG elements. You can upgrade your characters by collecting orbs dropped by defeated enemies. At the end of each level, you can use the orbs to make Aya more powerful. Sometimes the enemies drop red orbs; if you collect enough of them, you turn into a demon. Your attacks become more powerful, but they also take away from your health.