The only ways to obtain crystals is either by completing Daily Quests, or buying them with robux. You can also obtain crystals by completing premium tracks in battle passes.
Daily Quests give you 25 crystals per day if you complete all 3 of them. It is not possible to get any more than that in a day.
- If you decided to buy everything in the Cash Shop (excluding limited items) using only Daily Quests, it would take you 8 years and 156 days to get all of the required crystals.
- From the 26th to the 30th of November 2020 there was a 25% Black Friday Sale in purchasing crystals and Classes.
- It takes about 20 min to complete all daily quests, then you get 25 crystals, so that is about 75 crystals per hour. It would take 58+ hours of work to get 4400 crystals. Or you can buy it using robux, a few hours of minimum wage is faster than playing the game.