Hundreds of years ago Drahmin was a warlord who ruled a large empire. He eventually died...or was murdered...and was sent to the Netherealm where he was banished to 5th Plane for all the evil he commited.
His torture was so horrible he went completely insane and he became so consumed with anger and evil he transformed into an Oni. After turning into an Oni, he became one of the torturors of the damned and was the most feared and bloodthristy Oni of them all.
The only thing that keeps him somewhat calm is the mask he wears.

cool story, I have heard somewhere that it was the mask of Kun Pao(or something like that). Do anybody know what this mask is all about?

You guys can go here (scroll down to Drahmin):

http://www.angelfire.com/sd/scaifsal/mk/mechi.html

It has the MKDA krypt images about Drahmin's past. Personaly I think Drahmin's story is awesome, and if they ever do a prequel MK, they should defintely have him in his human warlord form...