Vadrik, Astral Archmage (PMID-248S) - Innistrad: Midnight Hunt Promos Foil

If it's neither day nor night, it becomes day as Vadrik, Astral Archmage enters.
Instant and sorcery spells you cast cost less to cast, where X is Vadrik's power.
Whenever day becomes night or night becomes day, put a +1/+1 counter on Vadrik.