Reverse the Polarity [Doctor Who] Horse {0}: Return Ghost Town to

{0}: Return Ghost Town to its owner's hand

which cost particular combinations of path types

{T}: Put a +1/+1 counter on Crystalline Crawler

Stage 2 — (4/1) Evolve

Set: The Brothers' War Commander Type: Creature — Demon Rarity: Mythic Cost: {5}{B}{B} Improvise (Your artifacts can help cast this spell

Reverse the Polarity [Doctor Who] Horse {0}: Return Ghost Town toSet: Doctor Who Type: Instant Rarity: Rare Cost: {1}{U}{U} Choose one Counter all other spells. Switch each creature's power and toughness until end of turn. Creatures can't be blocked this turn. You see, before you reactivated it, I reversed the polarity of the neutron flow.