Typal Confusion

As this enchantment enters, choose Charmer or Buster. • Charmer — At the beginning of your upkeep, tap up to one creature you control, then choose another creature an opponent controls. Gain control of that creature until end of turn if it shares a creature type with the tapped creature. • Buster — Whenever you attack, choose a creature type among creatures you control. Until end of turn, target attacking creature you control gets +X/+0, where X is the number of creatures of the chosen type defending player controls plus the number of creature cards of that type in their graveyard.