Domesticated Pets

The start of pet loyalty begins with domestication. Loyalty can be gained more effectively through "partnering" however. The difference is best exemplified in the Disney+ movie "Black Beauty" where a young woman gains the trust and friendship of a wild horse that is corralled. Becoming the first person to ride the horse, she claims the traditional term "breaking" is not accurate. A better term to describe the phenomena she claims is Partnering because they both had to learn how to make running together work.

Intelligent Pets

An exceptionally powerful creature or one that inherently has or achieves an intelligence of 4 or higher cannot effectively be domesticated. Instead our new term partnering describes the possibility of building loyalty with such creatures so you can run together. Partnering would start with a significant bonding event and a consistent pattern of trust, much like the optional loyalty rule in Chapter 4: Creating Non Player Characters in the DMG explains. For instance, a pseudodragon raised from an egg, or saving the life of a unicorn are possible events that could lead to an intelligent creature's loyalty. In contrast, the intelligent worg's precarious relationship with its goblin rider is based on fear and mutual benefit. But much like the evil NPC pretending to be an ally to the party, the worg can turn on its rider in a moment.

Maximum Pets

The maximum number of pets available for loyalty progression is 3. Use your Wisdom ability modifier for domestic based pets or your Charisma ability modifier for intelligent pets. If you don't have at least a 12 Wisdom or Charisma, you will gain no pet loyalty. No matter what your modifiers are 3 pets is still the maximum you can gain pet loyalty benefits from.

Pets vs. NPCs

A loyal pet is much like an NPC that has reached a high loyalty score. A loyal NPC can have its control transferred to a member of your party. However, if a controlled NPC is manipulated for the selfish gain of the party, the DM can revoke control. Similarly, at the DM's discretion, a loyal pet's control can be revoked if the pet is neglected or continually doing things against its nature. Alignment should also be considered. Pet Loyalty benefits are meant to reflect in a small, unique way the substantially greater power a loyal NPC can bring to your party.

Multiple Pets

All of these benefits should complement the rules defined under the Constitution Hit Points section in the PHB. In the case of a pet's demise, HP benefits gained remain for the character, but multi pet advantages will be unavailable. Multi pet advantages are not retroactive like the Constitution ability modifier changes.

Limited Telepathy

At level 10 Loyalty, the bond formed with a pet is so great, even pets unable to speak are able to communicate with their bonded character in a limited capacity. When visible within 50 feet they are able to accurately communicate simple ideas, emotions or reference past events they've shared. This unspoken connection is available to intelligent pets as well, transcending the need for spoken word at times.

Bonded Character dropping to 0 HP

Loyal pets can make a DC 10 Wisdom (Medicine) check to stabilize a bonded character reduced to 0 HP. At level 4 Loyalty, the bond is so great that pets (even tiny ones) can stabilize the character as the Spare the Dying cantrip 1/day. An intelligent pet may decide to perform the normal DC 10 Wisdom check for other party members, but a domesticated pet will likely flee or protect the body of a bonded character that has perished. A domestic pet won't attempt to stabilize other party members unless it has been specifically trained to do so.

Loyalty Benefit: Pet Feats

At Loyalty level 2 and higher, there's something special between you and your pet. Sometimes subtle, sometimes magical, choose a loyalty feat that best suits your roleplaying style and pet!

If a loyal pet decides to go full hero using the optional sidekick rules, it can have a major impact in the party dynamics. Sidekick pets should really be special, part of an epic story they seem destined to partake in. For the purposes of encounter difficulty and challenge rating, sidekicks are included in the party size and will share in the experience earned.

Pets in Combat

Lacking a class and without attack training, a loyal pet will only attempt to assist you or evade attack. Every creature however, even domesticated ones will retaliate with whatever offensive capabilities it can muster if it is cornered or sufficiently enraged. If no command is given, role play the pet with those considerations. Having a beast automatically serve as a trained attack companion is reserved for the Beast Master ranger archetype. A beast master's companion can benefit from pet loyalty, however.

Now certain domesticated animals are particularly good in combat. For example, war horses have undergone advanced training to effectively coordinate in combat with a mounted rider using its Trampling Charge to great effect. This training doesn't require loyalty however, and the training considerations are separate from the benefits discussed here. An untrained loyal pet can be commanded as a bonus action to flee or stay next to you only on the first round of combat and continues to maintain that action unless a role playing decision to act differently arises (for example, the character is reduced to 0 HP). If you or the pet are surprised for the first round of combat, the pet will choose to stay near. If a pet is commanded to flee, it will move or dash to a safe location, using whatever abilities it has at its disposal. Keep in mind the pet's natural tendencies when considering how to carry this out. If a pet is commanded to stay near, it will choose the dodge or disengage action to stay next to you.