phase 1 = talk with darion, darion will summon arthas, small dialog appear
phase 2 = players fight darion
phase 3 = darion is friendly now, he will summon arthas again
phase 4 = arthas will select blood, frost or unholy spec
phase 5 = players fight arthas with darion, arthas is casting blood, frost or unholy spells
report any bugs to me, I'll try fix it
my english is bad
READ THIS!
Pastebinarthas displayID: 24191
darion displayID: 27153
darion faction: 1866
darion NPC flags: 1
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darion ID: 100000
arthas ID: 100001
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you can change NPC IDs in script