Zanzibar
Asymmetric map feature a beach, open areas, walls, courtyards, structures, moving objects and vehicles. Great for CTF.

Ivory Tower
A private home converted into a public park, Ivory Tower is a decent-sized map with many small areas with multiple levels and an open courtyard. Good for Slayer FFA or small team games.

Waterworks
Large map for big team games with lots of vehicles, featuring two fortresses separated by a large, wide-open area. There are also multilevel tunnels and teleporters. The center houses Forerunner machinery A good choice for 16-player, large team CTF games.

Lockout
A network of walkways over an infinite abyss, leading to a central platform. Lots of jumping. There are also fixed guns on this level, and the level is quite small.

Midship
Winding hallways and multilevel platforms inside a Covenant ship, the Begotten Angel. This map sounds like the return of Boarding Action, except with large see-saw in the middle instead of the abyss. You need to manipulate this object to get the Brute Shot, similar to the way that Zanzibar's fan conceals the plasma sword.