These maps can be found on Halo Waypoint via copying and pasting this to the browser until I can figure out how to create a link.
Maps:
Air Terminal - A faithful CoD:MW2 classic with a Halo twist. Good for FFA & Team Slayer and CTF.
Facility - GoldenEye
Purgatory - Close quarters chaos
Star Folly - Faithful remake of Red Folly from Halo Reach. Massive aircraft carrier now equipt with mantis's.