Pets
A worn pet adds stats. Pets have no levels: they have Growth, from 0% up to 200%, which rises as you hunt (some pets, such as the starting pet, stop at 100%).
Which pets
The basic pets , , and each raise one stat. They drop from monsters and come from the Pet Lucky Box.
Iron Condor (Magpie) raises Attack, Defense and HP; Red Scale Bird and the M33 pets raise all four stats (see Pet tiers below).
Wyvern, Sky Mirror and Unbound Dragon can be equipped at M33 (their [Support] and (PC) versions cannot).
Pet tiers
An 'M1 pet' is a pet you can wear from M1; the card shows the level a pet needs. At 100% Growth each stat is full: Attack +1,100, Defense +2,200, HP +2,200, MP +2,000 (x2 = twice that). From 100% to 200% every pet also gets extra Attack, up to +250.
A pet gives the same stats with every weapon, so for more damage pick one with Attack. M1 pets come from page 1 of Produce Pet at , M15 pets and Red Scale Bird from page 2; the pet you get is random, so for one particular pet buy it from another player. M1 and M15 pets can also come from at the same NPC (see crafting).
Growth
Growth goes from 0% to 200% (see it on the pet card); some pets, such as the starting pet, stop at 100%. Most of the bonus comes on the way to 100%; after that only the Attack bonus still rises a little. 200% is the end: after that the pet does not get stronger, so the next step is a higher pet (see Pet tiers).
Wear the pet and kill monsters that give you EXP: they also give your pet EXP. EXP Boost [Pet] () doubles pet EXP for 3 hours, adds 1% Growth at once, and Premium Service doubles pet EXP.
Activity no longer goes down over time (since the 206 update; mount activity too). from the Herbalist still fills it to the max: a pet at 0 needs one feeding, then it stays. At 0 the pet gets no EXP and its Attack bonus stops.
Selling and trading pets
Since the 209 update every tradeable pet can go on the Proxy Shop, Elite pets too (not bound, timed or rented pets), and the buyer gets it with the same Growth. A personal stall did not change: most pets (the basic pets and every pet you make at , Iron Condor too) still cannot go on it. Sell those on the Proxy Shop or face to face with Trade (both players need Lv 10, see trade-and-shops).
Wyvern, Sky Mirror and Unbound Dragon can also go on a personal stall, and they can be traded too (their [Support] and bound versions cannot).
A pet keeps its Growth when it changes hands. Bound pets, such as the pet a new character starts with, cannot be traded, put on a stall or dropped, but you can move them to your other characters through the account Warehouse at the Gate Master.
