LevelFirst place
E1M1 Hangar
E1M2 Nuclear Plant
E1M3 Toxin Refinery
E1M3 Toxin Refinery (Secret Exit)
E1M4 Command Control
E1M5 Phobos Lab
E1M6 Central Processing
E1M7 Computer Station
E1M8 Phobos Anomaly
E1M9 Military Base
E1M10 Sewers
E2M1 Deimos Anomaly
E2M2 Containment Area
E2M3 Refinery
E2M4 Deimos Lab
E2M5 Command Center
E2M5 Command Center (Secret Exit)
E2M6 Halls of the Damned
E2M7 Spawning Vats
E2M8 Tower of Babel
E2M9 Fortress of Mystery
E3M1 Hell Keep
E3M2 Slough of Despair
E3M3 Pandemonium
E3M4 House of Pain
E3M5 Unholy Cathedral
E3M6 Mt. Erebus
E3M6 Mt. Erebus (Secret Exit)
E3M7 Limbo
E3M8 DIS
E3M9 Warrens
E4M1 Hell Beneath
E4M2 Perfect Hatred
E4M2 Perfect Hatred (Secret Exit)
E4M3 Sever Thee Wicked
E4M4 Unruly Evil
E4M5 They Will Repent
E4M6 Against Thee Wickedly
E4M7 And Hell Followed
E4M8 Unto the Cruel
E4M9 Fear