General's Shieldsworn

You may cast General's Shieldsworn from your command zone. It costs an additional {2} for each
time you have cast a spell named General's Shieldsworn this game.
Sacrifice General's Shieldsworn: Target creature
gains indestructible until end of turn.
Whenever General's Shieldsworn is put into your graveyard, you may pay {w}{w}. If you do, put it
into your command zone instead.