Pawn

See also: betrayal

This is almost always a spoiler tag.
The only cases where this isn't a spoiler is when the player is made aware of the pawn nature, but the protagonist remains ignorant of it.

Essentially they're used as a pawn in another person's game.

Cases where the protagonist agrees with the goal should not count.

If this is part of their job, then this tag does not count (because it's their job). Unless the job is a ruse to accomplish something else (e.g. in case you're a freelancer of sorts). Exception can be done when the actual goal is veiled behind their job, so the work they actually do is not exactly in their job description (e.g. an engineer is told to install an electronic device which purpose they're lied about, later they find out it was actually a bomb or a hacking device or such).