The Monster Tamer archetype embodies a desire to reign in the threat of monstrous and magical animals, while simultaneously showing that such creatures are not as mindless as they are made out to be. Monster Tamer's adopt and rear baby monsters orphaned by adventuring parties and form a special bond with them. They raise and train monsters as they would any mundane creature, all while building a relationship of love, discipline, and trust. Once these tamed monsters are fully grown, they can make invaluable allies in the battle against relentless and indelible evils.

Monstrous Companion

At 3rd level, you are joined by a monster that you played a large part in raising. The monster acts as your companion as it accompanies you on your adventures, and is trained to fight alongside you. Choose a monstrosity that is no larger than Medium of challenge rating 1 or lower, with an intelligence of no more than 3. Add your proficiency bonus to the monster’s AC, attack rolls, and damage rolls, as well as to any saving throws and skills it is proficient in. Like any creature, it can spend Hit Dice during a short rest to regain hit points.

The monster obeys your commands as best as it can. It takes its turn on your initiative, and only takes actions on your command unless it is defending itself. On your turn, you can verbally command the monster where to move (no action required by you), and you can use a bonus action to verbally command it to take the Attack, Dash, or Disengage action. Optionally, you can have your monster companion use a special ability it possesses.

If you are incapacitated or absent, the monster acts on its own, focusing on protecting you and itself after completing the last command you gave it. The monster never requires your command to use its reaction, such as when making an opportunity attack.

If the monster dies, you can obtain a new companion by spending 8 hours a day for 3 days magically bonding with a monster that isn’t hostile to you and that meets the requirements.

Teamwork

Beginning at 7th level, on any of your turns in which you make a successful attack against a target, you can use your reaction to command your monster companion to immediately attack that target if it is within the monster's reach. Your monster companion has advantage on the attack roll. You can use this ability twice, regaining all expended uses of this ability on a short rest.

In addition, your experience raising, training, and living with monsters has vastly improved. The maximum CR of monstrosities you can bond with becomes equal to your ranger level divided by three, rounded down. The maximum Intelligence of the monsters you can bond with increases to 4.

Unbreakable Bond

Starting at 11th level, when you or your monster companion drop to 0 hit points, you have advantage on death saving throws while you are within 5 feet of each other. In addition, when you are reduced to zero hit points, your monster companion gains advantage on attack rolls, and a bonus to its damage rolls equal to half your ranger level rounded up against the creature that reduced you to zero hit points. It has disadvantage on attack rolls against targets other than the creature that reduced you to zero hit points, unless those targets are hostile creatures within 15 feet of you. This effect lasts until you stabilize at 1 hit point, or the creature that reduced you to zero hit points dies.

In addition, your experience raising, training, and living with monsters has made you a master of handling monstrosities. The maximum CR of monstrosities you can bond with becomes equal to your ranger level divided by two, rounded down. The maximum Intelligence of the monsters you can bond with increases to 7.

Indomitable Duo

Beginning at 15th level, the bond between you and your monster companion is familial, as if your very souls are connected. You and your monster companion have advantage on ability checks and saving throws while you are within 30 feet of each other. If you are about to be attacked by a creature within your monster companion's reach, your companion can use its reaction to impose disadvantage on the attack roll. If the attack misses, either you or your monster companion (your choice) may immediately make an opportunity attack against it.

In addition, your experience raising, training, and living with monsters has developed into a true affinity. Even intelligent monsters who are normally aggressive and violent towards humans recognize your love for monster-kind, and are less likely to attack you if you are by yourself or alone with your monster companion. When fighting a hostile monstrosity, you have advantage on Wisdom Animal Handling checks made when attempting to reduce that creature's hostility. The maximum Intelligence of monsters you can bond with becomes 9.