Lycanthropic Curse

Enchant double-sided permanent you control
Enchanted permanent gains daybound and nightbound. If enchanted permanent is a
creature, the flip side is a Werewolf in addition to
its other types. (Daybound permanents transform
when it becomes night, and nightbound permanents transform when it becomes day. If a player casts
no spells on their turn, it becomes night next turn. If a player casts two or more spells on their turn, it becomes
day next turn.)