While a few of them are quite tricky, most of them just manage to catch me off-guard. Considering I'm playing with three other players almost every time I start the game (usually my 13yr sister, 11yr and 9yr brothers) death by interference happens all the time. This is not even counting the times when we just decide to toss each other into the fire for kicks. Having someone land on your head while you are making a crucial jump or propelling off of someone else's while you are trying to maneuver in just the right way is the most hilarious way to die.
It looks like everyone else on the forum is finding the game easy though, so I might be the only one that's ever seen a REAL game over. You start at the beginning of the world (or where you last saved, some worlds let you save in the middle) with all of the powerups you've collected knocked back to zero. Its really nasty and I often find myself forfeiting (everyone goes in the bubble and its a forfeit) just to avoid getting a game over.
I really love the game, and I think the difficulty in multiplayer is just right for my family. It took us forever to get past 8-1 and 8-3 though. My sister actually managed to do 8-2 solo after the rest of us died. Meanwhile, I tried out the coin battle and its an absolute riot. All manner of interference is fair game, as I was trying to throw my sister into Boo so that I could get a few seconds on my own to collect coins. Meteor smashing her into the bottom of the screen giving me the lift I need to reach some valuable coins is fun too. There appear to be a few levels specifically maid for coin battle, including one that starts out with a blatant homage to Mario Bros... the last Mario game to get the coop treatment; and the first Mario game by name.
