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.
Is Combining one single Interrupt, or are all addings of further RA/MA/Fears announced as single interrupts?
So is it:
1. RA/MA/Fear 2. All Combines 3. Turtle's Shell etc. by oppononent
Or 1. RA/MA/Fear 2. 1st Combines 3. Turtle's Shell etc. by oppononent/ if not then> 4. 2nd Combine 5. Turtle's Shell etc. by oppononent/ if not then>
1. RA/MA/Fear 2. 1st Combines 3. Turtle's Shell etc. by oppononent/ if not then> 4. 2nd Combine 5. Turtle's Shell etc. by oppononent/ if not then>
This is the appropriate sequence for multiple effects combining.
Combining those "attack effects" and The Turtle's Shell's ability are both Interrupts, and follow the action round procedure of each player getting the opportunity to take an Interrupt or pass.