Black Tailed Mongooses in the North Maiz Prairie area are easy to farm for exp because of their predictable attack pattern. Simply open with a regular attack, then use a 'Counter, Defend, Counter, Defend' loop until they die. Even a level 1 pet can pull this off, as long as you don't mess up the loop and get yourself hit.
'Angry' Black Tail Mongooses give extra exp compared to the regular ones, so only hunt those. By playing as your pet, you get more exp than if you played as your main character with the pet just alongside.
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