Each day, you can complete daily quests to collect 5 chests.
These quests are simple enough to do without having to spend anything.
You get 5-100 keys depending on the quest difficulty.
You can collect chests at 20 keys, 40 keys, 60 keys, 80 keys and 100 keys.
The rewards from each chest increase in quality and you can collect
gems and a meteorite from the 100 keys chest.