Vanta's most vulnerable emotion is fear, This results in the corrupted form having more of an effect on his mind (personality, mindset, moral compass, etc.) Though they change form while corrupt, it's just a set of green stripes in his fur, and a different eye color
Song used: Evacuate(Friday Night Incident) Documentation describes the black ace as an inverted seaweed in terms of fur color, otherwise, he fights with a hybrid of Seaweed and Persian Tactics. Those who witness the black ace noted a lack of agression towards them, however all attempts to attack resulted in a counterattack leaving them crippled, all without using a megaform in the process...
