The Unicorn Trooper is a unit released on April Fool's day 2015. Interestingly enough, this unit only takes 20% fire damage, which makes it a decent unit against the Ancient Sentinel, should players dispatch the Ranged Weapon System and Melee Weapon System quickly.
This unit has been in the game files for a long time, prior to its release. It was first mentioned by AveryCloseCall in 2013 as an April Fools joke, however, since then, has come a long way from being a joke; gradually earning attack animations and even statistic information.
This unit was also mentioned in the 3.0 Dev Diary as a Boss Strike reward for a test run Boss Strike named "Gantas's Revenge", used by game developers for testing the Boss Strike system.
It has an extremely large damage range for its second attack, Wild Swing, so players should be cautious when using this attack as it has a possibility of dealing a very low amount of damage.