Watch TV Series Unicorn Warriors Eternal Adult Swim Online Free. Unicorn: Warriors Eternal follows a team of ancient heroes protecting the world from an ominous force. Throughout history, unicorns have symbolized the virtuous, appearing to ensure that goodness reigns. When the reawakening of our heroes comes too early, they find themselves in the bodies of teenagers. Damaged as a result, their memories of who they are and the history of the unicorn over the centuries have been lost, with some of their magical abilities weakened and fragmented. Not only do they have to protect the world against the prevailing darkness, they have to do it while navigating the unexpected laughs and humor that come with teen angst and emotions.