Fiendsmith's Sanct - The Infinite Forbidden (INFO)

If you control no face-up monsters, or the only face-up monsters you control are LIGHT Fiend monsters: Special Summon 1 "Fiendsmith Token" (Fiend/LIGHT/Level 1/ATK 0/DEF 0), also you cannot declare attacks for the rest of this turn, except with Fiend monsters. If a face-up "Fiendsmith" monster(s) you control is destroyed by an opponent's card effect, while this card is in your GY: You can Set this card. You can only use each effect of "Fiendsmith's Sanct" once per turn.