Garukai

In Garukai you play as general Troy MacGoop, captain of the Leonarda, last vessel of humanity's fleet against the Zogh invasion. Embark for a great journey across the infinity of space with your crew and discover the terrible past that haunt you through a powerful story of revenge, love and redemption. Customize your ship, meet new crew-mates and build an army as you make your last stand against the invader. Garukai is an action packed open world centered around player choice that will make you rethink what it means to be alive.

"You can do anything" - IGN

Just kidding.

You orbit around a planet thingy and shoot aliens thingies.

Use the left and right arrows to move. Pressing right makes you orbit clockwise and turn purple, allowing you to shoot the purple aliens, left makes you orbit counter-clockwise and turn you green to shoot green aliens.