Highland Reel and Churchill will join Caravaggio on the Coolmore stallion roster after they compete at the Breeders' Cup meeting at Del Mar.
Commonwealth Cup winner Caravaggio was Coolmore's original choice for the $10 million Everest at Randwick earlier this month before his winning run came to an end in the July Cup.
Highland Reel, who finished third to Winx in the 2015 Cox Plate, will defend his title in the Breeders' Cup Turf (2400m).
Dual Guineas winner Churchill will run against the world's highest-ranked horse, Arrogate, in the Breeders' Cup Classic (2000m) on dirt on Saturday (Sunday AEDT).
The 2018 northern hemisphere breeding season begins early in the new year.