Let's talk about placing markers during fights.

[Sove92]

Yeah. The concern I have though is what about fights where the scenery changes? Like say Zurvan where the first phase is in one spot, then transitioning into phase 2 you 'fall down' to a new platform. Or Shinryu etc where you're taken to a different platform.

While this is a yikes level change for any fight that physically changes the fight arena, such fights are rare and only Shinryu, Thunder God and Engels come to my mind right now (Chrysalis and O3 also count for this, but you have no reason to waymark in those anyway). Most of the time, like Zurvan, Byakko, Seiryu, Ivalice Ultima, it's just smoke and mirrors and you never actually leave the starting platform.

This is also really bad news for those wanting to (re)clear UCoB, as the fight becomes way more difficult without markers mid-combat.