Pets are various friendly creatures. The selected pet accompanies you and helps in combat. Finding a pet is not easy, most often it can be obtained as a reward for completing the game season.
The pet's universal passive skill will suit any class. In addition, each pet will be able to improve the spells of a certain class, suitable for that particular pet.
The selected pet gains experience along with you and gradually gets stronger. Visit the Jaeger in New Heim to unlock or upgrade your pet's skills.