At the WCS Finals event last weekend there were a lot of big reveals. Chris Sigaty told us what was coming in the future of StarCraft 2 while on-stage Blizzard revealed the cinematic and release date of the final expansion for the game. However, slipping in under the radar was a small tidbit - the Allied Commanders mode that was originally revealed at Gamescom has been renamed to simply "co-op missions."
Lead Designer Jason Huck told me during our interview that they were renaming it because "there was confusion there between Archon mode and it and which was was which. Plus we want people to understand what that mode really is."
Having had it pointed out, I could see the two being confused very easily by players unfamiliar with StarCraft. When two players are acting as one controller in Archon mode, they are certainly allied commanders. He said that this name was also far more descriptive of what the nature of the mode was, given it operates like, and sometimes is a direct port of, the campaign missions, only designed to be played by two people.
Huck also mentioned it was one of the things coming in Legacy he was most excited for players to get their hands on. He sees it as filling a gap where players who were intimidated by online play would find nothing to do after completing the campaign other than trying the next difficulty up. It gives those with regular teammates a reason to stick with StarCraft rather than moving on to a MOBA or somesuch too.
On the design side, a little more life is injected into the ludicrously overpowered unit designs that inhabit the campaign. They could never be brought over to competitive multiplayer, but co-op will allow them to be used in an environment that isn't tied to story and will be different each time it's played.