Online Arena

The Online Arena
This is more or less what you'd expect it to be. You go online and battle your friends (if you have any with the game), or you can choose a Ranked Match if you'd like and it will pair you up with a random person.

The problem with the way this is set up is that it doesn't pair you based on the levels of your Micromon. Usually the people who are in the Arena doing ranked matches have extremely high levels. Unless you think you can get lucky, or have your own high-level Micromon, you will likely lose several times before you ever win.