Investi-gator

When a creature dies, you may sacrifice a creature with converted mana cost 3 or less. If you do, investigate. (Put a colorless Clue artifact token onto the battlefield with "{2}, Sacrifice this artifact: Draw a card.")
{t}, Sacrifice two Clues: Detain target creature. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)
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