Epic Games is counter-suing Silicon Knights, accusing the Too Human developer of attempting to "take Epic's licensed technology, pay nothing for it, and use it any way it pleases."
Silicon Knights is currently suing Epic, accusing the Gears of War developer of failing to provide a final development kit for the Unreal Engine technology.
But according to Epic, Silicon Knights had complete access to the Unreal SDK and the company's support network for up to nine months before it entered into a licensing agreement, reports GameSpot.
Epic also claims that Silicon Knights' game engine, which it built to continue the work on Too Human and an unnamed title for Sega, is unauthorised and derivative work that violates its licensing agreement.
Epic is seeking damages of at least USD 650,000 and an order that will see any code and games that infringe the copyright to be destroyed.