Vigilance (Attacking doesn't cause this creature to tap.) Whenever a creature enters the battlefield under your control, if its power is greater than Sharp-Eyed Rookie's power or its toughness is greater than Sharp-Eyed Rookie's toughness, put a +1/+1 counter on Sharp-Eyed Rookie and investigate (To investigate, create a colorless Clue token. It's an artifact with ", Sacrifice this artifact: Draw a card.").