"No matter the cost, I must discover the source of these strange happenings."

Daring Sleuth

When you sacrifice a Clue, transform Daring Sleuth.

Bearer of Overwhelming Truths

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever Bearer of Overwhelming Truths deals combat damage to a player, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Daring Sleuth // Bearer of Overwhelming Truths

When you sacrifice a Clue, transform Daring Sleuth. 

 Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever Bearer of Overwhelming Truths deals combat damage to a player, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Daring Sleuth // Bearer of Overwhelming Truths

Creature — Human Rogue // Creature — Human Wizard