All models in this force gain the Sworn Protector (Théodred) special rule.
Riders of Théodred
Captains of Rohan, Riders of Rohan and Rohan Royal Guard treat Théodred as if he were Théoden for the purpose of their Arise Riders of Théoden special rule.
Fight in Ranks!
Friendly Rohan Infantry models armed with throwing spears may use them as standard spears in addition to their normal use. However, if a model uses their sear as a throwing spear in a turn, they cannot use it as a standard spear in the same turn.