It's a Biological Fact

 is the ninth episode of the third season and the forty-seventh overall.

Synopsis
The Reds, Tucker, and Caboose meet with Tex on the beach near O'Malley's fortress, where she reveals her plan to destroy both O'Malley and the entire base by planting a bomb inside. Tex has scouted the base and found the exact location to place the bomb. However, citing the bomb's immense weight, she has someone else carry it; of the others, only Caboose can lift it. Meanwhile, the Red Zealot informs O'Malley and Lopez that a crowd of people is gathering on the beach. Upon learning that Lopez is inside with O'Malley, the Reds balk at destroying the base, but Tex refuses to risk losing her chance to defeat O'Malley. Tucker solves the problem by reminding the Reds that, since Tex is a mercenary, they can simply hire her to help them to retrieve Lopez. Tex agrees to this arrangement for a future favor.

Trivia

 * In the episode Caboose must carry the bomb because he's the only one strong enough. However, as Assault (where players must carry a bomb into enemy territory and detonate it) is a team game, only solid red or solid blue players can be seen in the same shot with the bomb.