How about Charmander in quicksand

hmm... perhaps some tar pits?

or perhaps sinking Zavok?

true.. i've never done tar pits all that often (they're really hard to do ngl haha)

I personally like the idea of sinking in quicksand as part of a commute, and acting like it's no big deal.

I like to imagine Bowser has a big moat of mud in his castle deep enough to submerge him up to his horns, and he wades through this moat from end to end on a regular basis. He could easily breathe through his nostrils if he just tilted his head up a little, but he's too stubborn for that. He'll keep his nose under and march forward with pride, even if it means he comes close to drowning by the time he finally emerges.

Or maybe he has to tour his jungle fortresses, but he left his clown car at home and the pipes are all clogged, so he has to go from fort to fort by foot, passing through deep quicksand on the way, and acting like he isn't bothered at all by it.

Or perhaps he just sees a bridge over quicksand and refuses to use it.

that's so in character for bowser and i love every second of it.

Tar pits are underrated, you should draw more that.

Maybe tar kobolds.