Prime World: Defenders is now available on Steam, offering a tower defense game set in the same continuity as Prime World, their upcoming strategy/RPG. Here's what this is about:

Prime World: Defenders merges classic tower defense gameplay with a collectible card game mechanic. Your towers, your spells, your traps - all are magic cards that you can collect and upgrade as you progress through the campaign. You'll have to develop your own strategy for each map, because you earn random cards at the end of every battle. Will you have a plan that fits your own particular hand? Choose your deck wisely as you move forward.