Companion characters will function similar to the way the NPC allies did in the earlier Knights of the Old Republic games, acting as AI-controlled "companions." Players will only have one companion character out at a time, and they can be swapped in and out from the player's pool of allies.
While they may sound like traditional MMO "pets," the team is trying to make them feel more like compelling, dynamic allies.
"Companion characters--we want them to be more than pets," said creative designer James Ohlen. "We want them to be virtual friends. We want you to interact with them and become friends with them."
"You're gonna be able to customize your companion character in different ways," Ohlen continued. "Your companion characters are going to be leveling up and getting different equipment."
The designer also explained how players will actually shape the way their companion characters develop. "If you are a Sith, your companion character is going to develop a lot differently than if you leaned more toward the light side."
There will also be plenty of interaction between the player and the companions. "You'll be able to form friendships, romance companion characters, or even to trade them," added Ohlen.