Pets
Pets are learned with souls (usually dropped by the same-named monster). Each learned pet gives the bonus of its genus, and the genus insight level unlocks slots with random effects. You can work out the bonuses in calculator.
How to collect all 200 pets and what they give — in the guide AION 2 pets. Every pet's progress in the game and its spawn points on the map are shown by TeamMate.
Cogni 41 pets
Per pet: Lv. 1: HP +10Lv. 2: HP +20, Critical Hit +1Lv. 3: HP +30, Critical Hit +2, Might +1
Family understanding: 9 effect slots, unlocking from level 1 to 9 level; effect grades: Common, Rare, Epic, Unique, Heroic.
Fera 65 pets
Per pet: Lv. 1: Mount Ground Move Speed +0.01%Lv. 2: Mount Ground Move Speed +0.02%, Accuracy Bonus +1Lv. 3: Mount Ground Move Speed +0.03%, Accuracy Bonus +2, Dexterity +1
Family understanding: 9 effect slots, unlocking from level 1 to 9 level; effect grades: Common, Rare, Epic, Unique, Heroic.
Natura 48 pets
Per pet: Lv. 1: Stamina +300Lv. 2: Stamina +600, Critical Hit Resist +1Lv. 3: Stamina +900, Critical Hit Resist +2, Precision +1
Family understanding: 9 effect slots, unlocking from level 1 to 9 level; effect grades: Common, Rare, Epic, Unique, Heroic.
Varian 46 pets
Per pet: Lv. 1: Mount Sprint Stamina Cost Reduction Rate +10Lv. 2: Mount Sprint Stamina Cost Reduction Rate +20, Evasion Bonus +1Lv. 3: Mount Sprint Stamina Cost Reduction Rate +30, Evasion Bonus +2, Constitution +1
Family understanding: 9 effect slots, unlocking from level 1 to 9 level; effect grades: Common, Rare, Epic, Unique, Heroic.
Special 7 pets
Family understanding: 9 effect slots, unlocking from level 1 to 9 level; effect grades: Common, Rare, Epic, Unique, Heroic.