Attain character level 90. This challenge still counts even if your character dies afterwards.
This.... requires a decent build to do. It requires around 2 weeks to reach this level, depending on how long you spend on the game each day and your skill level. If you are willing to spend a bit more currency to do more exp-rewarding content such as beachheads or breachstones or Zana map-modifiers, you're gonna level pretty fast. But of course, these strategies require at least a decent build that doesn't die too often …
If you are looking for decent meta builds, check out the poe.ninja builds for a good idea on meta builds and to check prices on unique gear and other items. The main Path of Exile subreddit and r/PathofExileBuilds are also good places to look for builds and helpful levelling / currency earning tips.
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