Have you or your players ever made any custom art/music etc. featuring aspects of your campaign...

I am heavy, weapons guys. And these, are my weapons.

Even if that were true, what's stopping you? Post it, pussy.

I was part of a PokeRP that occasionally threatens to start up again, and one of the girls drew this of (most) of our party as it was a running joke that my character had an unwanted harem.

As a general principle, I try not to post content that people don't want to see. Here goes nothing.
>(1/4)
Starting off with the one I'm the most proud of, since it was the first time I tried to draw something digitally.

This the stand I will be using in our group's next campaign, YMCA. It can spit itself and other things into 4 pieces by color: Red, Green, Blue, and Ultraviolet. (I needed a fourth color channel and couldn't think of anything better)

>(2/4)
All of the other stands I illustrated were made by me slapping stuff together in Photoshop.
This one is named TNT, its body is made of chunks of rock that explode when touched

>(3/4)
Another photoshopped standu, take a guess what this one did

>(4/4)
At some point, one of my friends commissioned the party and their stands. So I whipped up a bullshit title card in Photoshop

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After an arc where my group were dealing with asshole Regency wizards living in a flying city, they ended up running up significant debts by forging a major villain's signature to pay for repairs to their airship.

With the assistance of a weaselly wizard lawyer they prepared an invoice for the villain, which they served to him formally by the hand of Mr Slake, a nasty little clerk.