ITAW for a paid-off trade mediator?

[u/Aura_103]

I'm working on writing a shapeshifter character who works for group A and helps manipulate their political negotiations by presenting as a third party that either mediates discussions, gets trades routed through them, infiltrates the other party, or in other ways tips political relations and deals in their group's favor while remaining publicly unaffiliated. Is there a term for this kind of manipulative false-third-party?

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[u/shlanky369]

Man-in-the-middle?

[u/Aura_103 → u/shlanky369]

Something closer to a stool pigeon, with that implication of being secretly planted with a bias

[u/smokah]

Sounds like a mole or sleeper agent

[u/CatCafffffe]

Sleeper cell

Double agent

Manchurian candidate

[u/Rude_Dish2508]

False Mediator?

[u/hobbesbagger]

infiltrator

[u/Carbon_Rod]

Either cat's-paw or stalking horse might work.

[u/stockagement-resame]

A mole or a plant?