mercenary

palkkasoturi, palkkasotilas

rahanahne

kannattava puhekieltä One motivated by gain, especially monetary.
(quote-book)
A person employed to fight in an armed conflict who is not a member of the state or military group for which they are fighting and whose primary motivation is private gain.
(quote-book)| https://books.google.com/books?isbn=1605201243| author=(w)| year=1781 | passage=He exhorts the emperor to revive the courage of his subjects by the example of manly virtue; to banish luxury from the court and from the camp; to substitute in the place of the Barbarian mercenaries, an army of men interested in the defence of their laws and of their property| volume=3
puhekieltä One hired to engage in a figurative battle, as a corporate takeover, a lawsuit, or a political campaign.
motivate Motivated by private gain.
Dryden

For God forbid I should my papers blot / With mercenary lines, with servile pen.