Yes, I also tried the original Pixel Dungeon one time. Crazy hard mode.
For tips, hide behind doors for as many strikes as possible.
Try to enhance a Glaive with speed, from the Stone of Augmentation(stay with staff for mage). Then upgrade and add a glyph. Plate armour up to +4-6.
I tried for a day or 2 to get strafe-running, could not do it.
Would love to play Xonotic though, it has lots of old-school FPS flavour.