PFFFFFFF I'm actually still not sure whether Russel or Henry will be helping him with the mask uuuugh i need to work out timing of some stupid costume shenanigans with Henry's mun first to see if Russel would need to get brought in for help instead

As for the team-up, I think the way we should create a custom monster would depend on their powersets. Danny specializes in being sneaky, flying, and turning shit intangible and sticking it somewhere where it can't do further damage. What about Russel? I know he's got a piano but I'm not entirely clear on what exactly it is he can do? Based on that we can come up with something that would be really good for them to fight together.