A "terrific foil" refers to a person or thing that is very different from someone or something else but also complements or enhances their qualities. Full definition
Val Kilmer seems to be playing serious until a couple of face - to - face scenes when he cuts loose, and makes a terrific foil for Forte's nonsense. (dallasfilmnow.com)
Providing a terrific foil to Atkinson's slapstick antics is Peter MacNicol as the curator of the Los Angeles gallery; his harried and neurotic straight man makes a perfect Cousin Larry to Atkinson's twisted and demented (to the extreme) Balki. (themoviereport.com)
P.J. Byrne, as Okoye's pal, is a terrific foil. (slashfilm.com)