Can you use the reaction on Shiro Chugo when proclaiming honor in the dynasty phase?
Shiro Chugo and proclaim
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.
Can you use the reaction on Shiro Chugo when proclaiming honor in the dynasty phase?
Using the Proclaim ability is an action, so yes: you may use Shiro Chugo's Reaction at any time when a Proclaim action is taken.