Based on the Dance of the Dragons, then the obvious contender for another major battle in season 2 – assuming it comes at the end – would be the Battle of the Gullet. This is a massive sea battle that takes place between the Velaryon fleet and the Triarchy, who have around 90 warships. The battle comes as the Velaryons block access into Blackwater Bay while Otto Hightower schemes with the leaders of the Triarchy, and the result is one of the biggest sea battles in Westeros history (and, yes, dragons are involved).
There are a couple of factors that make me think this won’t be happening in season 2, even after Condal’s latest tease of what’s in store. Firstly, there hasn’t really been any hint of it in the trailers (that things like set photos haven’t shown it is less of an issue, as much of it would be filmed at Leavesden Studio). In an interview with THR last year, stunt coordinator Rowley Irlam confirmed a sea battle was planned, but it didn’t sound like it was immediately forthcoming.
