In Legends of Runeterra, if you want to get new cards and other rewards, you’re going to have to open chests. There are other mediums that rewards come through, such as capsules and wild cards, but Chests give the most bang for your buck.
Along with chests, there are also capsules and wild cards. In the case of chests, there are 5 tiers: Bronze, Silver, Gold, Platinum and Diamond, with each of them progressively giving better and better rewards.
There are two different ways to unlock chests. The first way is to select a region in the rewards tab and activate it. This will cause all experience earned to level up this specific reward tree and when you unlock chests, you will receive cards specific to the region that is selected.
The other way to gain rewards from chests is by unlocking your weekly chests. Weekly chests fill up when all experience earned, regardless of the region selected and come in sets of three. They follow the tier progression of chests mentioned earlier and are only able to be unlocked once every week. These chests consistently only need 1000 experience to level up.