Who are Grover Underwood's allies?

Grover Underwood, a satyr from the "Percy Jackson & the Olympians" series by Rick Riordan, has several key allies. His closest friends include Percy Jackson and Annabeth Chase, who support him in various quests and challenges. Additionally, Grover has strong ties with other characters from Camp Half-Blood, including Tyson, the Cyclops, and various nature spirits, as he is committed to protecting the environment and wildlife. Together, they navigate the dangers posed by mythological creatures and threats to the world.