Applegate Katherine Alice. The Animorphs 30. The Reunion

The book is known to have been ghostwritten by Elise Donner.Enjoying a day to skip school, Marco unexpectedly runs into his mother (Visser One), and discovers she is hiding in an office building, planning to find the Hork-Bajir colony. Marco, Tobias and Ax confirm this on a late-night visit, in which they negotiate a deal with Visser One. Marco begins to formulate a plan that will destroy Vissers One and Three, and free his mother, and make the Yeerks believe they have destroyed the Hork-Bajir colony. The plan goes well for the most part, but a few miscalculations reveal to Visser One that at least one of the guerilla fighters is human and there is a misconception that Jake and Cassie have died. When the Animorphs spring the battle between the two Vissers, Visser Three is forced to retreat and Visser One is believed to have perished (over a cliff, butted by Marco in mountain goat morph), though not before realizing that Marco is one of the warriors.Animorphs is an English language science fiction series of young adult books written by K. A. Applegate and published by Scholastic. It is told in first person, with all 6 main characters taking turns narrating the books through their own perspectives. Horror, war, dehumanization, sanity, morality, innocence, leadership, freedom, and growing up are the core motifs of the series.The story revolves around five humans, Jake, Marco, Cassie, Rachel, and Tobias, and one alien, Aximili-Esgarrouth-Isthill (nicknamed Ax), who obtain the ability to morph into any animal they touch. Naming themselves "Animorphs" (a portmanteau of "animal morphers") they use their ability to battle a secret alien infiltration of Earth by a race called the Yeerks. The Yeerks are a parasitic race of aliens resembling large slugs that take humans as a host by entering and merging with their brain through the ear canal. The Animorphs fight as a guerilla force against the Yeerks, led by Visser Three, and their program to take over the human race. Morphing into animals allows them to battle the various armies of aliens that the Yeerks use, but it also protects their identities. As far as the Yeerks know, only Andalites like Ax have the ability to morph, and if they knew that the Animorphs were mostly human they would be able to easily find out who they are. Protecting their identities becomes more and more difficult as the series goes on because though someone with the ability to morph can change into any animal that they touch, they can only stay in a morph for two hours or they will permanently become that animal. Throughout the series, we see how the war affects the characters in different ways, mentally and physically.