What about a fun round where everyone has the kasta barrel gun and has unlimited barrels in them? Last person standing wins and most kills gets the most points.
I think falco's idea is better than just a straight 'magneto stick, off you go' round due to the large difference in skill at it. It'd be no fun for any newer players to get yeet off in the first few seconds by optimal or sweer lol. Maybe like OitC would work, kasta with 1 barrel and magneto stick, each kill is +1 ammo... but then again props are infamous for bad kill and damage registering. Either way, straight magneto method wouldn't work on vanilla, only a few maps with props and even fewer with props that can damage.