I just leveled up to level 4, yet only have 75 shadow crystals.
I will give you as much detail as possible as to what I have done from lvl 0 to 4:
At level 3 I used a reset to pick a new hero and deck, which says it shouldnt cost any shadow crystals or stop you from receiving them.
I played about half my games on the PC client (downloaded) and the other half on my android phone.
I level 0 to 4 having fought 2 different AI opponents.
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