The Behemoth is an enemy in Final Fantasy X-2.
They are a rather powerful enemy to deal with, except in Chapter 5, where they are ridiculously easy compared to the rest of the enemies the party can fight. They have well-balanced stats and absorption to Lightning-elemental attacks, making them harder to take down. Using Armor Break (if applicable) as well as hard-hitting physical attacks and having Lightning-resistant or absorbing equipment helps with dealing with this enemy.
In Oversoul, Behemoths will start targeting one character at a time with powerful physical attacks, so using Protect or a Light Curtain will help reduce the damage from those attacks. They are always found alone.
The Behemoth the player captures is a particular one named Behemoth, who hopes to realize his dream of selling balloons. Throughout his journey he receives help from Bombs, who tell him about different kinds of balloons, machina, who help him dig up air pumps in the Bikanel Desert, and the Hypello, who teach him how to inflate balloons. When released, Behemoth opens his own balloon-selling caravan in the Kilika Woods, but initially scares away other fiends due to his appearance. When the Kinderguardians approach Behemoth unintimidated and buy balloons from him, the other fiends realize there's nothing to be afraid of and buy balloons from him as well, satisfying Behemoth's dream.
Behemoth is a beast mentioned in Job 40:15–24. In addition to mythological creatures, it is likened to dinosaurs, especially sauropods, as well as hippos, rhinos, and bison. Metaphorically, the term behemoth denotes "an extremely large or powerful entity".