Earn some Skull Totems.

Find the Secret in The Cut.

Kill 10 Ridden with a Skull Totem.

Complete All Ridden Hives.

Kill each of the Warped Ridden.

Kill a Monstrous Breaker after removing all of its armor.

Kill an Ogre with the Howitzer.

Find the secret in Plan B.

Form a party in Fort Hope.

Good luck out there, you're gunna need it.

Safely descend the ladder in the construction zone in Resurgence.

Find the secret in Dr. Rogers' Neighborhood.

Complete a level while getting at least 50 kills with melee weapons.