瞬间
探查,然后你每操控一个线索,目标生物便得+1/+1直到回合结束。(探查的流程是将一个无色线索衍生神器放进战场,且其具有「

,牺牲此神器:抓一张牌。」)
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.
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.
No player may take any action in between the two steps of Confront the Unknown, so the target creature will get at least +1/+1.
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.
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.