Fille Fantôme, Grim Maiden.

Friends in low places - As long as Fille Fantôme
is in the command zone or on the battlefield,
Zombies, Skeletons, Spirits, and Vampires cost {1} less to cast.
{p/b}{p/b}, tap all untapped Zombies, Skeletons,
Spirits, or Vampires. All Zombies, Skeletons,
Spirits, and Vampires gain +1 +1 counters