Crown Achievement in Vampire Survivors

Leveling up is done by collecting blue (and eventually green and red) crystals that enemies sometimes drop after killing them. You'll essentially need to lure enemies around in circles, more or less, so that you can circle back and pick up the crystals they dropped, allowing you to level up. Once you reach level 10 in a single game, this will unlock. Leveling up to level 10 is a pretty low goal compared to other achievements, so you will likely even get this in your first or second game.