Smash run

What it is
Smash run is a mode where you and your friends are in a giant arena defeating enemies to gain power-ups, just like in Kirby's air ride. Once you're in the giant arena, you only have five minutes to defeat as much enemies as you can for power-ups. There are bigger power-ups, which give you more ability, depending on the power-up. Once those five minutes are over, you and your friends use those power-ups to fight in a stage. There are enemies from other games, like Stalof, enemies from Donkeykong, and even enemies from past Smash bros. games.

Screen shots
Here are a few screen shots. As seen here, there are power-ups for arms, speed, attack, defense, jump, and special attacks.

Here we have Donkeykong beating up enemies for power-ups.

Here is a map of the arena. It tells you if you got a power-up, and what kind.

Here is the results screen, it shows what power-ups you have.