Hey guys did you see the new post from 
Now available in ranked play
We're excited to announce that you'll now earn loot chests when you reach a new higher league tier for the first time in each ranked play season. The further you advance, the better the rewards!
Loot chests are awarded only on your first promotion to a tier during the season. For instance, if you move from Bronze 3 to Bronze 2, you'll get 3 loot chests. However, if you drop back to Bronze 3 and then return to Bronze 2 later in the same season, you won’t receive another set of chests.
A list of the "League Tier Advancement Chest" which is divided into minor, major and Ultimate, where you can see in the image the prizes to be distributed in which one do you hope to compete?
You can use potions to increase the chances of winning gold and legendary ones.
We can see the detailed drop rates of our chests, to try our luck to get one of them and win something spectacular.
In this tab from the game we can see the probabilities from a better angle.
Are you eager to get your hands on one of these chests and try your luck, let's go