Co-op mode is simply a mode where you can get a friend to help you with 1-Player modes over Wifi or directly.
Over an Internet Connection
Over the Internet, you can get friends to help you with the Home-run Contest game mode and the Multi-Man Brawl game mode.
At Home
You can get a friend to help you with the Subspace Emissary, All-Star Mode,Boss Battles, Target Test, Home-run Contest, or Multi-Man Brawl
Subspace Emissary
The Character allowence stays the same but each play gets 2 characters rather than 1 player getting all of them. This can make things easier or harder depending on the stage the players are on. If they are on a stage that has lots of emenies, this can help because there are twice the amount of people helping to defeat the emnemies and one more person that they have to gang up on. But on other stages such as bosses Co-op can be a burden because if, for example, [[Tabuu] uses his off waves attack, both the players may be KO'd thus losing the players 2 charcters rather than just one.
All Star Mode
If two players attempt to do All Star Mode, they will go though the normal format with a few minor changes such as:
- The final foe-Olimar now has a a second Olimar to help him out
- If one of the players is KO'd, the other player cannot continue on his own, it is as if both players have been defeated
- Instead of having 3 heart containers, the players now have five, the two extras bein below the platforms that hold the normal three
- At the end of the event, you get a combine two-player score instead of the two scores being recorded onto both the characters, although you recieve both the trophies.
Boss Battles
Like All Star, Boss Battles has a very simalar format to 1 player Boss Battles but has a few slight differences such as:
- Like All Star, if one player is KO'd, the other may not carry on by his or herself
- Also like All Star, there are more Heart Container
- Again like All Star there is only one final score rather then two to be recorded onto the character.
Target Test, Multi Man Brawl and Home-Run Contest
Target Test, Multi Man Brawl and Home-Run Contest are pretty much the same only there are two people playing rather than one.