Guardians of Orion has a variety of classes also known as "Guardians", each with varying weapons and abilities.
So far, Guardians of Orion has 9 playable guardians which can all be unlocked with an in game currency called "Trek Credits" (TC). This can be earned by completing various achievements, daily quests and weekly challenges. Alternatively, some guardians will automatically become available to the player depending on which edition of the game they purchase (please note: Guardians of the previous edition are also included).
Below is a list of the different Guardians and the Edition to which they become unlocked: