The Watchful Patrol

Begin the game with this card revealed.
During your upkeep, detain target nonland
permanent. Only creatures you control
have "Enrage-when this creature is dealt
damage investigate."
Sacrifice four Clue tokens; detain target nonland
permanent. When a creature you control dies,
you get a 2/3 white and blue Human token
with vigilance, first strike and "when
this creature deal damage
to a player, they reveal their hand."