From Compendium of Worldly Lore
This is a prestige class meant for ranger types, as it sort of fall in line with most ranger builds, or druid is a solid option. If you want to basically play pokemon this is the class for you as you make monsters your friends and get stronger monsters as you gain more power.
Role: DPS
Characteristics: A DPS with monstrous companions to fight next to.
Source: Dungeonscape
Game Rule Information
The Beast Heart Adept has the following game statistics.
Abilities: Charisma for your monstrous empathy and Strength to be good in combat or Dexterity.
Alignment: Any
Hit Die: d8
Starting Gold: N/A
Class Skills
The Beast Heart Adept's class skills are Climb (Str), Concentration (Con), Craft (any)(Int), Diplomacy (Cha), Handle Animal (Cha), Heal (Wis), Jump (Str), Knowledge (arcana)(Int), Knowledge (dungeoneering)(Int), Knowledge (nature)(Int), Knowledge (the planes)(Int), Profession (any)(Wis), Ride (Dex), Search (Int), Spot (Wis), Swim (Str), and Wilderness Lore (Wis)
Skill Points at 1st Level: (4 + Int modifier) × 4
Skill Points at Each Additional Level: 4 + Int modifier
Class Features
All of the following are class features of the Beast Heart Adept.
Weapon and Armor Proficiency: A Beast Heart Adept is proficient with whatever they were already proficient with.
Monstrous Companion Ex: You gain the service of a monstrous companion. The creature is similar to a druid’s animal companion, but it is a magical beast or aberration rather than an animal. Choose one of the following as your monstrous companion: ankheg, blink dog, giant eagle, giant owl, hippogriff (4 Hit Dice), krenshar (4 Hit Dice), otyugh, owlbear, pegasus, or worg. Except for the hippogriff and the krenshar, which are larger than normal, the monster is typical of its kind. If its Intelligence is greater than 2, the companion has the same alignment as you. If you have levels in other classes (such as druid or ranger) that give you the ability to have an animal companion, those levels do not stack with your beast heart adept levels for the purpose of determining which kinds of monstrous companions you can select (and what the abilities of those companions are). At 3rd level or higher, you can select from alternative lists of monsters (see the sidebar). Just as with a druid’s alternative animal companion, an alternative monstrous companion gains abilities as if your beast heart adept class level were lower than it actually is.
Monster Empathy Ex: You can use body language, vocalization, and demeanor to improve the attitude of a magical beast such as a chimera or a gorgon. This ability functions like the druid’s wild empathy class feature, except that it affects magical beasts regardless of their Intelligence score. You can also use this ability to influence an animal (such as a dire bear) or an aberration that has an Intelligence score of 1 or 2 (such as a rust monster), but you take a –4 penalty on the check. If you have the wild empathy ability from another class, add your levels in that class to your beast heart adept level when influencing magical beasts or animals. In addition, you no longer take a penalty to your monster empathy check when influencing animals. If you have 5 or more ranks in the Handle Animal skill, you gain a +2 bonus on your monster empathy checks.
Monster Handler Ex: You can make Handle Animal checks with regard to magical beasts and aberrations without penalty. This ability applies only to creatures that have an Intelligence score of 1 or 2. Magical beasts and aberrations that have higher Intelligence scores cannot be controlled by Handle Animal at all.
Monstrous Lore Ex: At 2nd level, you gain uncanny knowledge about all types of living monsters, including their habitats, behavior, abilities, and weaknesses. You can make a special monster lore check to identify monsters or their special abilities or vulnerabilities. The check functions as a Knowledge check, except the monster lore check can identify any living creature. You gain a bonus on this check equal to your beast heart adept level + your Int modifier. You can attempt this check in addition to making the relevant Knowledge check to learn about a creature. If you have levels in the bard class or the loremaster prestige class, you can add those levels to your beast heart adept levels when determining the bonus on the monster lore check.
Monstrous Flank Ex: At 4th level, you learn to better coordinate your attacks with your monstrous companion. When you form a flank with a companion, both you and the creature gain an additional +2 bonus on attack rolls and damage rolls against the flanked opponent.
Extra Monstrous Companion Ex: At 5th level, you gain a second monstrous companion, chosen from the list of companions available to a 1st level beast heart adept. Treat your beast heart adept class level as if it were four levels lower for the purpose of determining the monster’s abilities (or of selecting an alternative companion at higher levels). At 9th level, you gain a third monstrous companion, chosen from the list of companions available to a 1st-level beast heart adept. Treat your beast heart adept class level as if it were eight levels lower for the purpose of determining the monster’s abilities (or of selecting an alternative companion at higher levels).
Monstrous Tactics Ex: Starting at 7th level, you and your monstrous companions make an excellent team. Through coordination and practice, you have learned to optimize your combined efforts. When one of your monstrous companions strikes an opponent with a melee attack, the target provokes an attack of opportunity from you. With this ability, you can make an attack of opportunity against a particular target once per round. In addition, your companions do not grant cover against your enemies when you use ranged attacks or spells.
Monstrous Team-Up Ex: When you reach 10th level, all the members of your adventuring party now gain the benefits of your monstrous flank and monstrous tactics abilities. Any references to “you” in those abilities now include your allies.