Complete area one.
Complete area two.
Complete area three.
Complete area four.
Complete area five.
Complete area six.
Complete area seven.
Complete area eight.
Complete area nine.
Complete area ten.
Complete area eleven.
Complete area twelve.
Complete area thirteen.
Complete area fourteen.
Complete area fifteen.
Complete area sixteen.
Complete area seventeen.
Complete area eighteen.
Complete area nineteen.
Complete area twenty.
Complete area twenty-one.
Complete area twenty-two.
Complete area twenty-three.
Complete secret area twenty-four.
Kill twenty enemies with the chainsaw in one session.
Kill fifty enemies with the shotgun in one session.
Kill fifty enemies with the chaingun in one session.
Kill twenty-five enemies with the rocket launcher in one session.
Kill twenty-five enemies with the plasma rifle in one session.
Find a BFG.
Have 200% health and armor.
Kill twenty enemies with the fist in one session.
Complete area one on NIGHTMARE! difficulty.
Complete area two on NIGHTMARE! difficulty.
Complete area three on NIGHTMARE! difficulty.
Complete area four on NIGHTMARE! difficulty.
Complete area five on NIGHTMARE! difficulty.
Complete area six on NIGHTMARE! difficulty.
Complete area seven on NIGHTMARE! difficulty.
Complete area eight on NIGHTMARE! difficulty.
Complete area nine on NIGHTMARE! difficulty.
Complete area ten on NIGHTMARE! difficulty.
Complete area eleven on NIGHTMARE! difficulty.
Complete area twelve on NIGHTMARE! difficulty.
Complete area thirteen on NIGHTMARE! difficulty.
Complete area fourteen on NIGHTMARE! difficulty.
Complete area fifteen on NIGHTMARE! difficulty.
Complete area sixteen on NIGHTMARE! difficulty.
Complete area seventeen on NIGHTMARE! difficulty.
Complete area eighteen on NIGHTMARE! difficulty.
Complete area nineteen on NIGHTMARE! difficulty.
Complete area twenty on NIGHTMARE! difficulty.
Complete area twenty-one on NIGHTMARE! difficulty.
Complete area twenty-two on NIGHTMARE! difficulty.
Complete area twenty-three on NIGHTMARE! difficulty.
Complete secret area twenty-four on NIGHTMARE! difficulty.
Complete area two from a pistol only start. [Hurt Me Plenty+]
Complete area three from a pistol only start. [Hurt Me Plenty+]
Complete area four from a pistol only start. [Hurt Me Plenty+]
Complete area five from a pistol only start. [Hurt Me Plenty+]
Complete area six from a pistol only start. [Hurt Me Plenty+]
Complete area seven from a pistol only start. [Hurt Me Plenty+]
Complete area eight from a pistol only start. [Hurt Me Plenty+]
Complete area nine from a pistol only start. [Hurt Me Plenty+]
Complete area ten from a pistol only start. [Hurt Me Plenty+]
Complete area eleven from a pistol only start. [Hurt Me Plenty+]
Complete area twelve from a pistol only start. [Hurt Me Plenty+]
Complete area thirteen from a pistol only start. [Hurt Me Plenty+]
Complete area fourteen from a pistol only start. [Hurt Me Plenty+]
Enter the exit room of level fifteen with a pistol only start. [Hurt Me Plenty+]
Complete area sixteen from a pistol only start. [Hurt Me Plenty+]
Complete area seventeen from a pistol only start. [Hurt Me Plenty+]
Complete area eighteen from a pistol only start. [Hurt Me Plenty+]
Complete area nineteen from a pistol only start. [Hurt Me Plenty+]
Complete area twenty from a pistol only start. [Hurt Me Plenty+]
Complete area twenty-one from a pistol only start. [Hurt Me Plenty+]
Complete area twenty-two from a pistol only start. [Hurt Me Plenty+]
Complete area twenty-three from a pistol only start. [Hurt Me Plenty+]
Complete secret area twenty-four from a pistol only start. [Hurt Me Plenty+]