Will wearing the Iron armor stop a personality from being able to use his cavalry trait to move into a battle?
Iron Armor and Cavalry
A topic from AEG's L5R CCG Rules forum, copied for Oracle of the Void from a copy of the forum saved in October 2015, so pages it didn't save are missing. Players' names are left out; the rules officials are named. Rulings are as they stood on these dates; later rulings, the rulebooks and the Rules Archive may differ.
Will wearing the Iron armor stop a personality from being able to use his cavalry trait to move into a battle?
No, because the Cavalry ability is a player ability, in the Rulebook.