Monster taming – Through magic or breeding, you managed to bend captured monsters their will. Be it giant spiders, wargs, big boars or any other monstrosity that roams your lands. These creatures are fast as well as extremely savage. (Light Cavalry gets an advantage)

Mythological beast taming –(Requires monster taming) Creatures of myth now let you ride them into battle. These things are more than simple monsters. Such beasts may be Erymanthian Boar, a Manticore or a Direwolf. There are far harder to train, far stronger to us in combat and will destroy any fool who stand in their way. (Heavy cavalry gets an advantage)

Skyward creature taming – (Requires Mythological beast taming) Your people managed to capture and breed a free creature of the sky. Maybe it was a gryphon, or a wyvern. It doesn’t matter. What does are the vicious claws that are now at your disposal in the skies. (You can make Aerial Interceptors and Fasts without requiring the Dirigibles trait)

The result of some brainstorming.