There are three tiers of familiars lesser, greater, and legendary.
The lesser familiars are more common. The lower familiars grow very fast, but since they mature faster, they are less able to harness the flows of magic and true strength. The lesser familiars are excellent companions for children. Since they are able to grow more quickly, they are capable of defending their master much easier. As their master gets older the relations switch and in the end the master will have to take the burden of being the main protector
The greater familiars are more powerful as they advance in age and experience. They are very slow to grow in their powers, but as they continue to gain experience, they will become equal to their masters in maturity. Their level cap is 20. Their true power lies dormant within until they are able to unlock it. They are not as capable when defending their masters in the beginning of their lives. They are not as common for children who depend on their familiar’s protection, so the greater familiars are seen more in wealthy households or cities where wild animal attacks are not as common.
Legendary creatures are rare creatures that most people dream about. These creatures are incredibly hard to get due to their fearsome attributes. The babies are hard to get away from their protective parents. Legendary creatures grow in different speeds depending on the creature and the dm’s discretion. These creatures are often seen as the pinnacle of the familiars. Because of their high risk in getting, they are very difficult to come by. Due to the cost of buying these mythical creatures only the very highest in society or the bravest can obtain legendary familiars. they can be seen by the sides of kings, lords, and the odd adventurer