Personal Info:
Real Name: Anthony Zerbe
Also Known As: No known Alias
Place Of Birth: Unknown
First Appearance: Strange Tales Vol.2 #9 (1987) Modern Age Villain
Known Associates: Mister Jip, Night
Group Affiliation: Agent of Mr. Jip, partner of Night
Base Of Operations: New York City, New York
Grudges: Cloak and Dagger
Creators: Terry Austin and Bret Blevins
Light Generation: Day has the ability to generate and release the unclean light/life energy he can sense in the 'impure' or those tinged with evil. The light can make the victim ill and may even kill them if they are exposed for a prolonged period.
The man named Anthony Zerbe was originally a petty criminal who lived in the worst streets of New York. This was until he was discovered by the creature calling himself Mr. Jip. Mr. Jip at some unknown time took him in as his ward and gave him superhuman powers over light. Mr. Jip had long wanted to make the hero Cloak the vessel for his essence. Day and his partner Night were tasked with the duty of separating him from his partner Dagger, hoping this would make it easier to obtain his obedience.
Day at Marvel Database
Day at Comic Vine