Roo-thless was a boxing kangaroo monster with a voice like Mickey Mouse and Mike Tyson, brought to life by Vilor, much against Nukus' wishes (though Vilor did tell Nukus that Les brought him to life). Monsters that were not brought to life by Nukus himself were uncontrollable. It took the unlikely teamwork of the Beetleborgs, Nukus and Horribelle to send Roo-thless back where he belonged.