MGE4M2: A Grave Mistake

A Grave Mistake is the second and final map of the Realm of Cultists in Dimension of the Machine. It takes place in the catacombs beneath the cathedral, Ranger stumbles upon an exact inverse of the cathedral floating in the void connected by tubes.

Secrets

 * 1) In the room with Scrags, Death Knights, pipes and acid pools, look at the yellow light on the ceiling. On either side of this light, there is a Shootable Button. Shoot both of these, then approach the yellow light, turn around, and look up to spot a third and final Shootable Button; shooting this one will open the secret compartment just below the yellow light, containing a Thunderbolt and two Boxes of Cells.
 * 2) Past the room with the first Secret, you will come across a corridor with Death Knights and Ogres; as soon as you open the doors, you should see a Shootable Button on the ceiling in between 3 dark patches on the ceiling. Shooting this will open a secret compartment to your left containing a Red Armor.
 * 3) In the more "hellish" looking section of this map (where you're inside the upside-down fortress with red sky all around), you will eventually come across a cracked stained-glass window with a Super Nailgun and Boxes of Nails in front of it. Shoot/hit this window to break it, carefully jump up into the now-open window and look down to see a very tiny platform under you. Carefully drop down to this platform for the final secret room, containing two small Boxes of Nails and a Quad Damage.