Tim Drake, Young Detective

Activated abilities of Clues you control cost {1} less.
{t},{w}, Sacrifice a Clue Token: Tap target
creature. It doesn't untap during it's
controller's next untap step. Investigate.
{t},{u}, Sacrifice a Clue Token: Target player
investigates. Investigate.
{t},{b}, Sacrifice a Clue Token: Target player
discards a card. Investigate.