He is not a typical unicorn, but evil and sadistic. He uses large broad sword against his enemies and wears red armor which about 20% cooler. He dislikes bronies.
After defeating the boss, you receive a Blue Chest as a reward. The Evilcorn may be defeated only once per timeline.
After defeating the Evilcorn for the first time, you receive an achievement "Clear Area XIV" which multiplies non-tap monsters' DPS by 1.02.