Her cavalry plan is set in stone. Her recruits will have to pay daily visits to their chosen stripes-lightening wolves. This will help deepen their bonds.
The stripes-lightening wolves might agree to sign a battle companion pact with their chosen warrior.
Mission completed.
A cavalry unit is born.
But, wait! Why should her military take extra care in protecting the defeated spirit beasts? Normal virtual games don't experience this annoying stuff. When a virtual beast's territory is conquered, the virtual beasts automatically submit to their conqueror. Or rather, when a virtual beast is beaten to a stupor. They offered themselves to the strong, who had defeated them. Such offerings might come in servant-master, slave-master, and so on relationships.