I played this game back in the mid 90's, in America, and I'm pretty sure it was for DOS.
Things I remember:
- You play as a knight in armor
- You start the game in hell on this platform at the bottom of a small pit, surrounded by lava
- You have a sword and a fireball spell
- It's first-person
- I think there was an orc or goblin on the cover art, and they were fighting a knight (probably the protagonist), and I think one of them had a spiked-flail-ball weapon thing
- Graphics were closer to Duke Nukem 3D than Doom
- Might've been a flaming skull enemy that shoots fire balls in the first room (the lava pit)
I never figured out the controls, so I didn't get far enough to be able to give more details.