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Nyxborn Unicorn

Enchantment Creature — Unicorn

Bestow (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached.) Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.) Enchanted creature gets +2/+2 and has mentor.