good games for a mini campaign?

hi everyone! i wanted to know if there’s a good ttrpg for a campaign on the shorter side - maybe 15-20 sessions or so? my dm is looking to take a break between our current campaign and the next, and id like to get some more dming experience. i don’t want to run an entire long campaign, however, and don’t want to do a bunch of one shots.

we currently play dnd 5e, and we LOVE rp and character creation. a few of us also play VTM if that helps with our likes. i could just run a shorter dnd campaign but i think we’re interested in trying something new out!

thank you for the help!