Ancient Investigator

When Ancient investigator or another creature you control attacks investigate.
When you sacrifice a clue token place a suspicion counter on target creature.
As long as Ancient investigator is in play and a creature has 3 or more suspicion counters on it that creature is detained
{w/b}{w/b}{w/b}: Exile target creature with 3 or more suspicion counters on it.
Sacrifice 5 clues: put Ancient investigator from your command zone into play