Lady Imperia of Ryten

Lady Imperia of Ryten gets +1/+0 for each
creature you control.
{t}: Destroy target permanent, activate this ability
only if you control 4 or more creatures.
{3}{w}{b}{r}, {t}: Return Imperia to its owner's
hand, create 3 1/1 Red Knight creature tokens
with "When this creature dies it deals 1 damage
to any target"