Game Mechanics Event/Extra Bosses in the Underworld

[NebulousOfficial]

Have you noticed that after defeating the Wall of Flesh, the underworld is virtually useless? There are no events with special hell monsters in the underworld. WoF is the only boss exclusive to the underworld. All weapons involving the underworld are strictly early hardmode unless it is a material to a future late game weapon (i.e. Molten Sword). It'd be nice to have something that revolves around the underworld after, say...Plantera?

 

[Acamaeda]

There are actually a few Hardmode weapons and things. You can get the Hel-Fire Yoyo from any enemy (this is not the same as the Cascade from pre-HM), and after beating a mech boss, Red Devils spawn which drop Unholy Tridents and Fire Feathers which can be used to make flame wings. It's not a lot, though, so some new content could be nice. Idk about an event or boss, but it should probably at least have something similar to the amount of things the Underground Desert or Underground Snow get in Hardmode.