Acornelia, Fashionable Filcher (UND 31)

Legendary Creature — Squirrel • Mana cost: {3}{B} • Unsanctioned • Rare

Whenever you cast a spell with a squirrel in its art, you get {A} (an acorn counter).
Whenever a Squirrel you control enters or dies, you get {A}.
{2}{B}, Pay X {A}: Target creature gets -X/-X until end of turn.
{G}, Pay X {A}: Target creature gets +X/+X until end of turn.

Illustrated by Bram Sels.