After completing all 5 of the mastery skills a candle will light above each of the pillars, Grandpa's letter will be removed, and a hat will appear on the pedestal between the combat and the foraging mastery pillars. There will also be a message saying "You feel Grandpa's hand patting your shoulder... "
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After unlocking all 5 masteries, a candle will light above each of the pillars, Grandpa's letter will be removed, and a hat will appear on the pedestal between the combat and the foraging mastery pillars. There will also be a message saying "You feel Grandpa's hand patting your shoulder... "