Feldon Windslasher, who headed up the Rebuilding the Spires event has shared their insight into why we did not see a “Grand Finale” to the Spires Event:
Congratulations on finishing the spire!
While it would have given me great pleasure to have an epic-x4 dragon with 20 million hitpoints spawn and attack you, that simply would not have fit the theme or lore of this event. The idea here was to let everyone on the server contribute in a 100% cooperative effort that permanently affects the game world. So the bosses that attack the spires during construction have a lore reason to exist, and were intended to be beatable by a small pick-up raid. The real reward for completing one of these spires is the permanent teleportation portal that opens up in the middle platform. It’s a reward for the entire server, that anyone can use.
Now, I absolutely love competitive raid gameplay, but I couldn’t justify setting up this event as a race to spawn the boss mob for server-unique rewards and eternal bragging rights. It just would not have made sense in this case. I certainly want to make events like that in the future, but this one isn’t a copy of the old Kingdom of Sky prelude.
and in another thread:
I remember the Kingdom of Sky prelude event, and the intent behind this event was much different from the previous one. While there are some contested epic spawns, they don’t give rewards that are unavailable to other participants. Everything you can take away from this event is purchased from the Quellithulian merchant.
I personally feel that enough precautions were taken, that a contested mob at the end would not have left hurt feelings like the Kingdom of Sky event did. Otherwise there is no question a ton of work went into making this event work.