you were right about the hall of fame, but it seems there's a limit, because blizzard is blizzard.
if you already have the non-gold version of legendaries crafting the golden ones won't give you any profit.
-scenario 1: you have sylvanas and rag, and get +1600 profit when the rotation hits
-scenario 2: you have sylvanas and rag, but decide to craft a golden one for 3200. when the rotation hits you get +3200, but they don't give you anything for the non-golden versions, so you're at 0. afterwards you can dust the gold one, then you're at +1600
-scenerio 3: you don't have sylvanas or rag. you should craft a gold one, get the refund, you'd be at 0, dis it and get a +1600 profit.
sceneraio 1 and 2 are the same since you end up with no gold legendaries and the same dust.
Dust will only be awarded for copies up to the maximum number of cards you could put in a deck:
-Maximum of 1 copy for legendaries - Ragnaros the Firelord, Sylvanas Windrunner
-Maximum 2 copies for all other cards - Conceal, Ice Lance, Power Overwhelming, Azure Drake
-The refund will prioritise golden cards over non-golden cards.
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