Whittle down the lesser demons to disable the Mancubus’ shield, superheat its armor to break it with a Shield Throw, and then kill the Mancubus to receive the Armor Upgrade.

Unless you're built like a heavyweight WWE wrestler, accurately sized Doom Slayer armor would probably be a little too big for you.

In the first large combat area of the level (with the Gore Portal on the western side), you’ll encounter an armored Pinky Rider amidst the dozens of other demons. Superheat the armor to destroy it ...