Frozen Valley 3v3
Justin Rouse, a skirmish map designer, dishes out some info on Frozen Valley:
Frozen Valley was the first 3v3 map designed during the development of Halo Wars. After Chasms, this was probably our most played map through internal playtesting. The layout went through one major tweak throughout development and that was the opening down between the teams that runs along the bottom edge on picture shown here. The first iteration had the hole as well as the mount near that bottom edge of the map extend all the way to the edge. Leaving a pocket only access through the middle by land units. It allowed the two bottom player on each team to build up safely.
As map “hooks” came online I wanted them to be easily attacked from different angles and only having 2 paths between teams was making this too difficult. Once the bottom side path was opened leaving a “3-way” go between the teams, along with the hooks placed on the map, more strategic options became available and the map became extremely fun. Before, it was just a fairly straight forward map.
Duncan Stanley, Community Manger for Robot, talks about Frozen Valley:
Frozen Valley was actually one of my least played maps during development. When it came to playtesting, I was usually available for the 1v1 and 2v2 playtest sessions (where I'd throw down with Thunder), so I rarely got to play Frozen Valley. Nonetheless, my incessant whining about the OPness of the Warthog got it toned down (yes, you read that right) before launch. Warthogs during development were almost immune to infantry up until RPGs entered the equation.
But on to Tactics! Your strategy for the game usually depends on if you're in the pocket (the middle) of your side or not. If you are, it's usually safe for you to boom and go for higher-tech units, possible swooping in to save the day at the last minute. If you're on either of the sides, you're usually in the thick of it with your opponents across the way fairly quickly over the expansions. As always, trying to grab your opponents nearest base is a good tactic to throwing their game off, if a bit risky.
Also, all the extra bases around the map mean that if you can protect them, you can get a ton of resources and build up armies very quickly. Personally, I like to go air if I'm Anders, or Tanks if I'm Forge on this map, they seem to cover the distance very quickly and can usually survive long enough for you to accomplish your goals with them.