Adventure EXP comes from Daily Activities, story quests, requests, Free Hunt research objectives, and Energy-consuming Hunt Requests. Daily Activity rewards reach up to 3,600 Adventure EXP at 120 Activity.
Adventure Rank gates story progression and Ecological Rank Ascension Challenges. Some challenges also require Proof of Mastery progress.
Higher Ecological Rank raises progression caps and unlocks harder hunts and higher-star monsters. Rank increases also grant rewards. See Level Caps for thresholds.