Alternative Levels

Levels from the Alternative Branch are denoted with "-A" written after the assigned number. Some believe these levels are parallel versions of their counterparts, while others believe these levels belong to a whole different spectrum of levels which co-exists with concurrent levels.
Level 0-A - "The Complex"
Level 1-A - "The Foundry"
Level 2-A - "Narrow Passageways"
Level 3-A - "Maintenance Halls"
Level 4-A - "Office Workrooms"
Level 5-A - "Abandoned Utility"
Level 6-A - "Concrete Dusk"
Level 7-A - "Submerged in H20"
Level 8-A - "Perilous Biotech"
Level 9-A - "Wreck of 09"
Level 10-A - "The Invertscape"
Level 11-A - "The Lavender Labyrinth"
Level 12-A - "High-Security"
Level 13-A - [NO DATA]
Level 14-A - [NO DATA]
Level 15-A - [NO DATA]
Level 16-A - “The Locker Rooms”
Level 17-A - [NO DATA]
Level 18-A - [NO DATA]
Level 19-A - "Radioactive Exemption Site 01"