Simple question, but my rules-fu and search-fu fail me. My understanding of Gidayu Sensei, the combine rules, and Naval are as follows:
Naval rules, p. 56, Comprehensive rules:
Naval: Players have the following ability relevant to Naval cards, known as Naval Invasion: Engage: If you are the Attacker, you have the first opportunity to take a Battle action, which must come from a card in a Naval Personality’s unit. Passing that action does not count toward ending the action round.
Combine rules, p. 46, Comprehensive Rules:
A way to use similar actions from cards in the same unit to create a larger strength effect. [...]
Combining starts with an original action that creates an attack effect from a card in a unit. As an Interrupt to that action, the player may use an ability from another card in the same unit that is appropriate to the phase and that creates another attack effect of the same kind. The player pays that ability’s costs, then resolves its action’s effects, with one change: instead of creating a separate attack effect, each of those actions’ relevant attack effects adds its own strength (with any modifications) to the strength of the original attack effect.
The original attack effect may only target a card that it, as well as each of the combining actions, could target. All other characteristics of the attack effect come from the original. You may combine more than one attack effect with the same initial action.
Because only the original effect actually targets the card, [...]
Gidayu Sensei Oracle MRP:
Interrupt, w: One of the action's Ranged Attacks may be combined with one Ranged Attack action from your target card in any unit.
Naval gives me the first opportunity to take a Battle Action. This Battle Action must come from a card in a Naval personality's unit (e.g., a Spearman on a Tsuruchi Gosho).
I can then interrupt this Battle Action with Gidayu Sensei's Interrupt, allowing me to combine a RA from another unit (e.g. Tsuruchi). As I understand the Combining Rules, this enables me to, as an interrupt, add the strength of Tsuruchi's RA to the Ranged Attack Action of Gosho's Spearman. The fact that Tsuruchi doesn't have Naval is irrelevant: "Naval" has no impact on the targeting of the RA, and the the Naval Engage Action does not restrict the interrupts that may be played in response to the Battle Action. Naval only restricts the initial battle action that I take (and subsequently interrupt) to an action in a Naval Personality's Unit.
Am I understanding this interaction correctly, or have I missed something glaringly obvious?
Thanks!
Max
Edited to confirm it was Gosho's Spearman with the RA