I've finished playing through Episode 1 (Knee Deep in the Dead) of The Ultimate Doom whilst finding all of the secret areas, collecting all of the items and killing all the things.
I've played through Episode 2 (The Shores of Hell) but not succeeded in finding all of the secret areas.
Like each of the DOOM episodes, there are nine levels - eight normal levels and one secret level in each - but I didn't find the entrance to the secret level in the second episode.
The nine levels in 'The Shores of Hell' are;
- E2 M1: Deimos Anomaly
- E2 M2: Containment Area
- E2 M3: Refinery
- E2 M4: Deimos Lab
- E2 M5: Command Center
- E2 M6: Halls of the Damned
- E2 M7: Spawning Vats
- E2 M8: Tower of Babel
- E2 M9: ??? (Secret Level)
Where are all of the secrets in The Ultimate DOOM Episode 2 - 'The Shores of Hell'?