Creature — Human Rogue
2 / 1
When you sacrifice a Clue, transform this creature.
Bearer of Overwhelming Truths
Creature — Human Wizard
3 / 2
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever this creature deals combat damage to a player, investigate. (Create a Clue token. It's an artifact with "

, Sacrifice this token: Draw a card.")
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.