6. Super Mario 35
Now in all honesty I could have put any "battle royale" mode here and called it a day, simply because when your only real enemies are other humans, it becomes very easy to hate them. However, Super Mario 35's brilliantly executed game mode does something that these other titles don't, namely that on top of punching you in the face through other players being absolute dicks, this also warps your nostalgia and makes your muscle memory betray you.
To better explain, think of it like this. We've all played the original Super Mario Bros. right? The opening few levels are ingrained into the public consciousness, so much so that we could likely do some of these blindfolded. However thanks to every other player being able to flood your stages with enemies you'll suddenly be on the back foot, and having to react to once beautifully designed stages becoming an absolute hellscape filled with flying Koopa Troopers, endless Goombas and even a Bowser or two to spice things up.
It's absolute carnage, and while being a lot of fun, will leave you cursing every other player as you get swamped.