I won with each hero but still won’t unlock any chapter, it says (You need 3 pack to unlock)
Only the first chapter is free, you have to purchase the others if you haven’t already. You should be able to do so with gold
you may need to buy three packs from its set(Rise of Shadows), don’t waste gold unless you find conformation or have spare gold and don’t mind buying 3 packs. I wouldn’t know cause I’ve unlocked it when it was introduced so I don’t remember