It's missing some depth in level and enemy variety, but the build synergy possibilities are vast and having so many unique stats that affect success and many, many different starting character traits provide a wealth of opportunity for fresh runs. I appreciate that a typical Wave 20 run can be completely knocked out in 30 minutes or less. Having a defined amount of time to plan around is fantastic for a filler game, but it's also quite easy to slip into hours straight of gameplay. It's just so much fun, and often hilarious. A great entry in the survivor auto-shooter craze.