Advanced format ruling
Fog King
Card effect (current official text)You can Tribute 1 monster, or no monsters, to Normal Summon (but not Set) this card. The ATK of this card becomes the combined original ATK of the Tributed monsters. Neither player can Tribute cards.
Current rulings for this card are maintained by Konami.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Advanced forum — sourced change requests get reviewed.