Celestial Bastion is a 4v4 map created for the launch of Heart of the Swarm in season 2 of 2013.
Official Map Description[]
The rush distance on this map is rather short, but there are many expansions you can take. It's possible to play a defensive game using your main choke point and securing the two Xel'Naga Towers.
References[]
Blizzard Entertainment. StarCraft II. (Activision Blizzard) Map: Celestial Bastion (in English). 2016.