When I Reserve Mirumoto Jaikei into the battlefield, fully invested, my opponent uses Interrupt the Void's Flow to negate the action (and go poof). What happens to the money I put into the pool?
Mirumoto Jaikei and Negation
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.
When I Reserve Mirumoto Jaikei into the battlefield, fully invested, my opponent uses Interrupt the Void's Flow to negate the action (and go poof). What happens to the money I put into the pool?
As described here (and here), when paying the gold cost of an action, you may produce gold; you may then spend that gold, together with gold from your pool, on the action. Any gold you don't spend on the action (and which isn't required to be spent on a particular cost, such as that produced by Honored Sensei when you choose to activate the trait) goes to your pool.
This all happens in the Pay Costs step of the Action Sequence - that is, before the Interrupts step, when Interrupt the Void's Flow is played.
To Recruit an Invest'd Jaikei, you must spend 15g on the action, plus any extra gold for any weapons costing more than 4g. Once spent, this gold is gone: you do not get it back if the action is negated.