Sinspawn on the S. S. Liki

[Skyblade]

So, on the first boat, between Besaid and Kilika, there is a room that Gatta and Luzu block you from entering, and they themselves are preparing for Operation Mi'hen. So... Is there a Sinspawn in that room? Is the reason Sin shows up to attack because they're already transporting the Sinspawn, and Jecht is drawn to them?

[Darth Ganon]

Are you also blocked from that room between Kilika and Luca? I don't remember.