E1M4 (Return to Phobos)

E1M4 is the fourth map of Return to Phobos. It was designed by Michael Kelsey.

Secrets

 * 1) From the blue key (which is located in the north-east in the area with various paths inside columns over a blood floor), jump south, east, south, east, north then turn and jump east then north to a platform containing a supercharge and an imp (two imps on hard skill). (sector 114)
 * 2) Just south-east of the exit is a long east-west room with a megaarmor at its east end.  The eastern wall here is a secret door leading to a room with a chainsaw and (in multiplayer only) four rockets. (sector 46)
 * 3) The very north-west area of the map (with the nukage pit containing a supercharge and other health and armor items) contains a secret door on its south wall leading to a room with a teleporter to a room with a supercharge (which can be lowered using a switch).  Both of these rooms count as secrets.  The trigger line for the door to the former is the step leading to two health bonuses in the west of the north-west area – however, this step is too high to cross, so only 50% secrets and only 88% items are obtainable. (sector 89)
 * 4) See #3. (sector 85)

Bugs

 * The map has red doors but no red key. The map can still be completed, however.
 * The map has a yellow key but no yellow door.
 * Some secrets cannot be reached (see above).

Current records
The records for the map at the Doom Speed Demo Archive are:

The data was last verified in its entirety on December 9, 2021.

Player spawns
This level contains seven spawn points:
 * 1) facing west. (thing 224)
 * 2) facing north. (thing 225)
 * 3) facing west. (thing 227)
 * 4) facing south-west. (thing 228)
 * 5) facing south-west. (thing 237)
 * 6) facing west. (thing 417)
 * 7) facing west. (thing 523)

Things
This level contains the following numbers of things per skill level: