It is a standard 1v1 sized map with a rough "S" shape with the starting bases at each tip and two bases on each curve. The bases are all Flood controlled but are not defended by tentacles as on Release. The Flood spits out infected marines and occasionally infection forms. In some areas there are Flood Eggs that release Infection Forms when shot. In the center is a Forerunner Spire of Healing and in the center of each curve is a Forerunner Bonus Reactor.
Because the Forerunner Bonus Reactor nearest to your base is not likely to have to be defended against the enemy it is often easy to take early if you can fight the Flood. Also to mobilize a large attack against you they must pass by it so it can be used as a lookout as well. As with Release using infantry often leads to failure because of infection by the Flood. Using fast vehicles or air units is often the best method because they navigate through the "S" shape without difficulty and slow vehicles must pass by enemy bases or reactors in order to reach their main base giving them ample time to prepare defenses. The Forerunner Spire of Healing is often a main focus because enemy bases cannot be attacked without passing so camping troops there can be a very useful lookout. One strategy is to use the UNSC Cobra and unpack them at the Spire creating a nearly impenetrable defense that can stop a Scarab in its tracks and then be healed afterwords to be fresh for another attack.
- Barrens and Frozen Valley are the only levels in Halo Wars to feature the Forerunner Spire of Healing.
- It is the first map to feature the Flood Egg.
- Some players have noticed that it resembles an "S" similar to how Memorial Basin resembles an "X".