One of the truly satisfying things with Doom and Doom 2 is that the levels were all designed with two playstyles in mind. Each level, starting with the pistol, you can either beat par on Hurt Me Plenty, or kill 100% on Ultraviolence. Most of the harder levels require some route-planning or lateral thinking to achieve that. All of which, back in the day, provided me with way more gameplay than you’d expect.