E1M1: Outer Prison
E1M2: Communications Center
E1M3: Waste Disposal
E1M4: Supply Depot
E1M5: Armory
E1M6: Training Facility
E1M7: Xenobiotic Materials Lab
E1M8: Outpost Quarry
E1M9: Nutrient Recycling
E2M1: Elemental Gate
E2M2: Shifter
E2M3: Reclaimed Facilities
E2M4: Flooded Installation
E2M5: Underground Hub
E2M6: Hidden Sector
E2M7: Control Complex
E2M8: Containment Cell
E2M9: Fortress 31
E3M1: Land of the Lost
E3M2: Geothermal Tunnels
E3M3: Sacrificial Bastion
E3M4: Oblation Temple
E3M5: Infernal Hallows
E3M6: Igneous Intrusion
E3M7: No Regrets
E3M8: Ancient Lair
E3M9: Acquainted With Grief
E4M1: Maintenance Area
E4M2: Research Complex
E4M3: Central Computing
E4M4: Hydroponic Facility
E4M5: Engineering Station
E4M6: Command Center
E4M7: Waste Treatment
E4M8: Launch Bay
E4M9: Operations