Sherlock Holmes

Whenever a creature you control dies, investigate. (Create a colorless Clue artifact token with "{2}, Sacrifice this artifact: Draw a card.")
Whenever you sacrifice a clue, detain target creature an opponent controls. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)
"My name is Sherlock Holmes. It is my business to know what other people don't know."