So Collab’s exist and I’m not one for hosting them. However I’m pretty good at coming up with ideas for ones and wouldn’t mind trying it out. Here’s my idea that someone else can host and get the credit for:
It’s called the ‘Last Stand Collab’. It’s a battle to the death between your RHG and your arch nemesis user (yes you can batter the living daylights out of everyone’s favourite Bullet that Explodes if you want). Sounds quite average right? Wrong!
Your RHG must be a torn up and damadged version with cuts, wounds, wires sparking or even arrows buried in their shoulders.
Another thing is no cataclysmic weapons of total annihilation so no Nukes, Super Sayins, Black holes…
The last thing is that both users must DIE, yes you both lose in the end but at least that way no other user gets the feeling of “I should’ve won” because they both lost.

Hope someone of good skill finds a use for this and Good Luck!