Scarlet Hollow is the first and only secret level of Episode 1. It is accessed through the secret exit found in Dis Base. Completing the level takes you to The Abyss and can be chosen from the mission select afterwards.
Mission Summary[]

The AMC Squad has found a hidden passage in Dis Base while it was about to self-destruct, which lead them to the place known as Scarlet Hollow.
Gameplay[]
At the start of the level, grab the Flesh-Squirter and deal with the Satyrs, Shades, Hadespheres and Bruisers all around you. There's a fire armor behind the bricks where the Bruisers are attacking. Go across a bridge and deal with some Flesh Wizards before you start platforming, grab the Blood Staff if you ran out of ammo for the Flesh-Squirter. After you jump across, you'll enter an outside area. Jump across sinking platforms and rush quickly through the collapsing bridge. Grab the Stygian Warcannon and head inside, go down and jump across some lava streams. Grab the red key, but be ready for an ambush from a bruiser and Hadespheres. Enter the door on your left, platform across the platforms and deal with Maephisto waiting for you in the hallway. Grab the treasure and a megasphere on your right and get ready to fight a Cyberdemon. Upon defeating it, a platform will rise to the exit portal, with two amulets on both sides.
Secrets[]

When you first get the Stygian Warcannon after the collapsing bridge, turn to the left to jump onto the archway, then jump around the column, then repeat for the next column, and then jump onto the broken column to obtain a Platinum Amulet. You can also sprint bunnyhop across the collapsing bridge and jump to the left at the end to get the same result.
Trivia[]
- This is the only location in Episode 1 where you encounter a Cyberdemon.
- This level replaced Doom Disco in the 10 year Anniversary edition.