3 / 4

: This creature gets +1/+0 and gains first strike until end of turn.
Daybound (If a player casts no spells during their own turn, it becomes night next turn.)

4 / 5

: This creature gets +1/+0 and gains first strike until end of turn.
: Creatures you control get +2/+0 until end of turn.
Nightbound (If a player casts at least two spells during their own turn, it becomes day next turn.)