You can only use the (1)st and (2)nd effect of this card’s name each once per turn.
(1) If you control no face-up monsters, or all 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.
(2) 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.