Fantasia, Soul Witch

Lifelink
When you cast Fantasia each player exiles a card
from their hand with a Soul counter on it.
you may play card with soul counter on them and
spend mana as though it were any type to cast
them.
At the beginning of your upkeep you may sacrifice Fantasia by paying 5 life. If she dies this way, the
next time you would pay Commander Tax its
applied as {b} instead of {2}