Dr. Mina Liao's Echo

Flying
{1}{u},{t}: Dr. Mina Liao's Echo deals 3 damage to any target.
{2}{u},{t}: Destroy target creature or planeswalker that has taken damage this turn.
{w}{u}{u}: Dr. Mina Liao's Echo becomes a copy of target creature or planeswalker until end of turn. If Dr. Mina Liao's Echo would die while copying another creature, regenerate it.