WASP-84 is an orange K-type dwarf (about 0.85 solar masses, 5,280 K, 0.77 solar radii), 101 light-years from Earth. WASP-84 c is a 15.2-Earth-mass planet, with an orbital period of 1.4 days, at 0.024 AU from its star, and an equilibrium temperature near 1,329 K, discovered in 2023 via transit. WASP-84 b is a 0.69-Jupiter-mass companion, with an orbital period of 8.5 days, at 0.078 AU from its star, and an equilibrium temperature near 732 K, discovered in 2014 via transit. Mutual gravitational tugs between the planets can slowly reshape their orbits, preserving clues to the system's assembly.