18 cards where (the card types include “horse” or the illustration contains “horse”) and the set is “otj”

Bounding Felidar (Outlaws of Thunder Junction #5)
Brimstone Roundup (Outlaws of Thunder Junction #115)
Bucolic Ranch (Outlaws of Thunder Junction #265)
Calamity, Galloping Inferno (Outlaws of Thunder Junction #116)
Caught in the Crossfire (Outlaws of Thunder Junction #117)
Caustic Bronco (Outlaws of Thunder Junction #82)
Corrupted Conviction (Outlaws of Thunder Junction #84)
Forest (Outlaws of Thunder Junction #285)
Great Train Heist (Outlaws of Thunder Junction #125)
Jolene, Plundering Pugilist (Outlaws of Thunder Junction #210)
Miriam, Herd Whisperer (Outlaws of Thunder Junction #221)
Mobile Homestead (Outlaws of Thunder Junction #245)
One Last Job (Outlaws of Thunder Junction #22)
Rise of the Varmints (Outlaws of Thunder Junction #179)
Smuggler's Surprise (Outlaws of Thunder Junction #345)
Soured Springs (Outlaws of Thunder Junction #264)
Stagecoach Security (Outlaws of Thunder Junction #30)
Take for a Ride (Outlaws of Thunder Junction #148)

The arc of my blade has carved a path of light to the end of these results.