Mission 40: Eliminate the Deserters

Mission 40 in Kingdom Hearts 358/2 Days is an optional mission that has Roxas once again eliminating a group of pesky swarming Heartless.

Regular mission
Eliminate the Deserters.

Story summary
Roxas once again goes after Deserters on behalf of the Organization.

Mission walkthrough
You will start out outside as usual. The chests in the outside corners are real treasure chests, but the one against the west wall is a Cymbal Monkey in disguise, so be aware. Whatever your choice, head into the Coliseum Vestibule, and then into The Coliseum. You don't even have to talk to Phil this time around to go in.

This time with the Deserters is a little different than in previous missions; they have invited their cousins, the Soldiers, along to play. Soldiers will keep re-spawning throughout the round, and won't stop until the Deserters stop spawning. So unless you are in the market for a massive heart chain, don't worry about the Soldiers and focus on the Deserters. You can choose to hit barrels into your enemies as well, but it's usually just more efficient to whack them with a decent Keyblade.

Once the mission is complete, be sure to grab the well-hidden Ordeal Badge towards the southwestern corner before leaving the Coliseum to RTC; this mission really doesn't take long at all.