* Fix spell 27808 (Frost Blast) used by Kel'Thuzad in Naxxramas. Triggered spell requires the original aura caster (Kel'Thuzad) as caster and not the targetted player.
* Full rework of Kel'Thuzad phase 1 in Naxxramas:
- Remove WotLK emote
- Use proper spells for summoning and spell logic
- Improve timers so that adds come more and more quickly, as they should
- Add visual effects on channeling
- Improve intro and encounter start flavour by adding and activating missing GO and spawning initial adds in three waves
- Initiate encounter through dedicated area trigger and not through LoS
- Change Kel'Thuzad combat start (he does not aggro until phase 2)
- Move almost all phase 1 control to the related periodic aura
- Fix adds AI: only those periodically summoned should aggro on spawn
Important note: Timers for periodic summon auras are guesswork based on severals original videos as WotLK sniffs are of no use here. Basic statistic analysis were used to define these timers but there are other solutions to that same mathematical problems. It is also possible (though unlikely) that auras stacks at some point instead of replacing each other. We will need Classic sniffs when available to improve this.
* Full rework of Gothik script in Naxxramas:
- Properly implement summoning of Unrelenting adds
- Correct timers
- Handle edge cases
- Properly reset stage to prevent Gothik from being stuck below his balcony on evade or adds to linger in the room
- Remove WotLK emotes
- Fix balcony phase for Gothik
- Revert central gate opening to what it was in Classic/TBC
