Traitor in our midst

[LabRat]

Inspired by RaidCastro's idea of incorporating rogue heroes in LNOEhere, I'm starting to have a vague idea of a traitor planted in an ATOE Cooperative game. This is new to me, so I don't have the concept fully fleshed out, but here's what I'm thinking of:

- Making use of the number tokens from LNOE or IFOS (I forgot if ATOE comes with this), each player draws one at random and keeps the number of the tile that they drew a secret.
- A D6 is then rolled, the result determines who the traitor is - this number revealed to everyone. This can result in none of the players being the traitor - which I think is better because I can only imagine a group of people having pointless paranoia
- The traitor then works against the group in secret - picking up Investigation tokens, doing actions that result in the Shadow track moving closer to darkness (is this possible to do in a Coop game?), hindering the group by obtaining and keeping helpful items and allies.
- A player may choose to investigate a fellow player at the cost of X Investigation. I don't know how much this should cost, but I imagine it should cost more to investigate a Hero than it does for a Town Elder. Investigating a Hero that turns out to be innocent will result in a penalty, and a reward if the investigated Hero turns out to be the Traitor.
- The Traitor can also opt to reveal himself once he decides that he's at an advantage. Once revealed, the Traitor can directly work against the Heroes - playing Event cards that hinder the Heroes, engage them in combat, etc.

Has a concept been introduced to ATOE before? I'm new to the game so I don't know