Makucha's Army is an army of evil animals led by both Makucha and Mama Binturong. Their goal is to get revenge on Lion Guard and eat every rare, exotic, weak, lame or sick animal from the Tree of Life. They're the main antagonists of Season 3.
After hearing about that the Tree of Life is real, Makucha and his leap try to lure the Guard into a deadly trap so they can catch Makini and interrogate her about the Tree's location. After the trap fails, his leap decided to give up so Makucha abandons his leap and starts his journey to the Tree of Life.
Mama Binturong infiltrates the Tree of Life by pretending to be a sick animal that Makucha and Chuluun were trying to eat. After gaining access, she gathers information and reports back.
Later, she hatches a plan to have Makucha, Chuluun, and Ora infiltrate the Tree of Life at dawn when the Night Pride are tired and finishing their patrols. Mama would act as a decoy calling for help on the other side of the Tree of Life which would distract the teams while Makucha's army would attack Queen Janna unencumbered. The plan backfires when Ono notices her slip-ups, and Anga sees from a distance that she's in no danger. Mama tries to get revenge on Bunga, but he easily repels her and reveals her identity to the Night Pride.
The Lion Guard and Night Pride force Makucha's army to leave once again.
Mama Binturong is the third addition of the group and the new leader of the group.
She joined after a brief struggle where Bunga emerges victorious and takes on Mama Binturong herself. He manages to take Makini's Bakora Staff and defeats Mama Binturong by passing gas and ruining her Tuliza stash. As Bunga flees the scene, Mama Binturong vows revenge. After meeting Makucha, Chuluun and Ora, she joins the army for feasting the rare animals at the Tree of life and as well as getting revenge on the Guard, particularly Bunga.
This is the third group of different species of animals. The first one was the Lion Guard, which lasted until the end of the series, and the second one was the disbanded Army of Scar. Unlike those groups, this is the only one that remained together and never disbanded.