Heretic

legitimately better than doom

basically single player Paladins

Didn't feel as tightly crafted to me as Doom, but the theming is a whole lot of fun, and the item system is interesting enough to go a long ways toward making up for weaker level design. My biggest complaints are that A) half the weapons are way flashier than their Doom counterparts, to the point that it actually makes aiming difficult at times (looking at you Dragon Claw), and B) this game made the baffling decision to take the most obnoxious enemies from Doom, the Lost Souls, and make them the most common mooks, then gave half of them a ranged attack on top of that. It's made a little better since this game natively supported vertical aiming, but I still hate that idea just on principle.