Mission 19: Eliminate the Deserters
Rare Heartless called Deserters have surfaced in Agrabah. Find them and eliminate them at once.
Roxas heads out on another solo mission to deal with Deserters.
You'll enter in Agrabah Street. You won't be attacked by Heartless here, so take plenty of time to snag any chests you can reach before heading to the Palace to confront the Deserters. When you are ready, enter the Palace area. You will fight two waves of eight Deserters each. The second will appear once you've defeated the first. When all the Deserters are gone, grab the chests and RTC. It doesn't come much simpler than that.
This is a great munny-earning mission if you find yourself short early in the game.
Just like other Deserter challenges, it's a matter of equipping a powerful weapon and smashing away as quickly as possible. The Deserters come to you, so this one takes a pretty minimal effort to reach three sigils.