Fat Princess vs Bowser. I can imagine Bowser trying to kidnap FP, thinking she is Peach who has "Really let herself go." They get into and argument about weight, which turns to blows.
Drake vs Wario. Drake is just about to get a treasure/artifact when Wario rides in on his mortorcycle and grabs it. He gloats about how much he can sell it for, prompting Drake to attack him.
Sweet Tooth vs Marth. Both normal guys (except for the whole flaming head thing) with bladed weapons. It's a battle of strength vs speed. I imagine Marth would simply mistake Sweet Tooth for a bandit and attack him. --- RIP City of Heroes and Paragon Studios - Killed by NCsoft. Not changing this line until Dimitri, Moosh, and Ricky appear in another LOZ game (7/20/09)
Although all of the others make sense, you kind of lost me on that one. --- Little Mac, Mega Man, Travis Touchdown for Super Smash Bros. 4. Street Fighter x Mortal Kombat, Shonen Jump vs. Capcom please.
The Kongs see Spike capturing monkeys and they think he's really trying to attack the jungle. This misunderstanding leads to Spike fighting either one of them. --- Little Mac, Mega Man, Travis Touchdown for Super Smash Bros. 4. Street Fighter x Mortal Kombat, Shonen Jump vs. Capcom please.