Zhan

When people die, they become ghosts. When ghosts die, they become Zhan.

Zhan originally lived in the fifth-dimensional space. In ancient times, to relieve a siege, a military strategist made a sacrificial pact with Chou Yan, the leader of the Zhan. He demanded that Zhan power be fused into the soldiers defending the city to end the siege. But Chou Yan wanted to gain freedom, so he released all the Zhan from the fifth-dimensional space. The city was saved from the siege, but the Zhan that had been released began to wreak havoc among humanity. By the time the strategist realized what had happened, it was too late. He could only use his life to seal Chou Yan away, but there was no way to seal the Zhan power or the Zhan themselves. People discovered that Zhan power could be used to kill Zhan, and that the descendants of those who wielded it would also inherit it. The released Zhan could also steal human lives and turn their victims into ghosts. And so began an endless war.