If the brain hood successfully hits a beast with an Intelligence of 3 or lower with its Slam attack, it latches onto the beast’s head and attempts to take control of the creature. The target must succeed on a DC 14 Intelligence saving throw or become bonded with the brain hood, losing all control of its body to the brain hood. While bonded in this way, the brain hood’s statistics are replaced by the statistics of the beast, including the beast’s hit points and Hit Dice, but the brain hood retains its alignment, personality, Intelligence, Wisdom, and Charisma scores, along with its Speak with Beasts trait. In addition, the brain hood retains its ability to cast spells. The brain hood can’t be targeted specifically while bonded with a creature. It can detach itself from the creature and end the bond by spending 5 feet of its movement. If the bonded creature is reduced to 0 hit points, the brain hood is ejected from it and appears in an unoccupied space within 5 feet of the creature.

While merged with a beast, the brain hood can communicate with beasts of the same type as if they shared a language.