- 1954Phantom StallionFilmRex's Horse
- 1953Iron Mountain TrailFilmKoko
- 1953Old Overland TrailFilmRex's Horse
- 1953Red River ShoreFilmRex's Horse
- 1953Shadows of TombstoneFilmRex's Horse
- 1953Down Laredo WayFilmKoko, Rex's Horse (as Koko the Miracle Horse of the Movies)
- 1952Colorado SundownFilmMiracle Horse of the Movies
- 1952Border SaddlematesFilmKoko - Rex's Horse
- 1952Old Oklahoma PlainsFilmKoko
- 1952South Pacific TrailFilmKoko
- 1952The Last MusketeerFilmKoko
- 1951Utah Wagon TrainFilmKoko, Rex Allen's Horse (as Koko the Miracle Horse of the Movies)
- 1951Rodeo King and the SenoritaFilmKoko - Rex's Horse
- 1950Hills of OklahomaFilmRex Allen's Horse (as The Miracle Horse of the Movies)
- 1940TyphoonFilmKoko