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Every time you level up, you earn Skill Points to use to buy upgrades for your character. You generally gain more points at higher levels, to compensate for the large jump in experience needed to gain that level. The earliest you can obtain this achievement is at level 15, where you should have a total of 504 Skill Points. Level 15 requires a little under 12,000 experience to obtain. Once at level 15 with 504 points, you need to spend at least 500 of them. If you don't have available skills to boost you to the 500 points spent marker, then level 16 is obtainable at just under 17,500 XP, with 570 Skill Points granted.

Most actions give some amount of experience. Digging, gathering resources, chopping trees, etc. Completing quests generally give XP as well. You can check your current level in-game by pressing . It will display your current and required XP, your level, a bar showing your progress to the next level, and your available/total Skill Points. Additionally, this screen has a "Allocate Skill Points" button in the bottom right. If you skip assigning points during a level-up, you can use that button to get back to the allocation screen.