Hexine, Mother of Shortstacks

Tiny Might (When this creature attacks, it can't be
the target of spells or abilities.)
{t}: Add {u}
Whenever you tap Hexine, Mother of
Shortstacks for mana, you may pay 1 life. If you
do, target creature gets -1/-1 until end of turn.
Whenever a Shortstack enters the battlefield
under your control, you may untap Hexine,
Mother of Shortstacks.