The horse and the men

For centuries, The Four Horsemen of the Apocalypse owned just one horse.
This arrangement worked out great for when there was just War or Death doing on, but sometimes there were two or three of them on that horse.
Or, when things were particularly bad, all four.
Not only was the load unbearable, but as civilization spread and got more complicated, they had a lot more ground to cover.
The lone horse didn’t particularly like that arrangement, so the gang got three more horses.
Nowadays, they each have several horses. And they’ve hired a full-time vet, trainer, and stable manager.