3 stars: A fun distraction for a while, but rapidly falls into grinding mode, and there are no offline grinding options to speak of. Without rewards like unique items and parts for completing levels, there's little incentive to finish the overly long boss battles instead of grinding base monsters for credits to buy the next upgrade.
2 stars: You walk your guy around and he shoots the things. Upgrade hp, armor, and damage with money earned. Buy drones with other money. Buy weird poorly explained upgrades with other other money. Dungeon doesn't unlock after completing level 5 with 20/20 boss kills and 3k/3k enemy kills. Am i missing something?
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