집중마법
생물을 목표로 정한다. 그 생물은 탭되며 조종자의 다음 언탭단에 언탭되지 않는다.
조사한다. ("

, 이 마법물체를 희생한다: 카드 한 장을 뽑는다."를 가진 무색 단서 마법물체 토큰 한 개를 전장에 놓는다.)
Clue is an artifact type. Even though it appears on some cards with other permanent types, it's never a creature type, a land type, or anything but an artifact type.
You can't sacrifice a Clue to pay multiple costs. For example, you can't sacrifice a Clue token to activate its own ability and also to activate Alquist Proft, Master Sleuth's ability.
You can't cast a spell without choosing legal targets. If all of those targets become illegal, the spell doesn't resolve and you won't investigate.
If an effect refers to a Clue, it means any Clue artifact, not just a Clue artifact token. For example, you can sacrifice Wrench to pay for Alquist Proft, Master Sleuth's activated ability.