Occasionally, a Legendary chest will appear in the shop and can be purchased for 500 gems. Conditions: Arena 10 or above for legendaries to appear in the shop This method is best if you want a specific legendary. Occasionally, legendaries will appear in the shop, purchasable for 40 000 gold. Conditions: Arena 2 or above to get a Super Magical chest, Arena 7 or above for legendary chest If you want to know EXACTLY when your Super Magical and/or Legendary chest will arrive, try. That means you have a 0.40% chance of obtaining a super magical/legendary chest from winning a battle.
You are guaranteed a Super Magical Chest, Legendary chest, and Epic chest every 500 chests. Attempt to obtain the chest from battle.However, Legendary chests are a feasible option, so that's included below. However, I'm assuming that you do not wish to pay a lot of money on this game, so I didn't include the option of purchasing Legendary King's chest.
There are many ways to obtain Super Magical Chest and legendaries.