The Academy regroups heroes from the eight playable major factions and the minor factions of the game. Heroes are mercenaries that players will unlock through actions in the game.
The Academy is stepping into a larger role in Endless Space 2 as it is positioned in a node of the galaxy, and therefore can be owned by a player. The Academy will also have a central role in the game’s background story.
https://wiki.endless-space.com/academy