Weary Prisoner // Wrathful Jailbreaker (VOW-184) - Innistrad: Crimson Vow: (Double Faced Transform)

Defender
Daybound (If a player casts no spells during their own turn, it becomes night next turn.)

Wrathful Jailbreaker attacks each combat if able.
Nightbound (If a player casts at least two spells during their own turn, it becomes day next turn.)