I have completed all levels on normal and am halfway through the game on heroic. Good news: I havent paid a dime. It requires patience to get the right cards to upgrade your towers but it can be done. Bad news: recently, the game has started crashing ALL THE TIME. Multiple times now (more than 10) Ive lost significant progress and, when youre not paying for upgraded cards, thats doubly frustrating. I really should just delete the game at this point since it keeps wasting my time.
FreckledFreyja about Defenders: Tower Defense Origins