operation that required the doctor to call in all eleven of his Egg Bosses from across the world, Eggman launched an assault to take back the refinery. Eggman managed to ward off Walter, even after being faced with a crystalline-controlled Crystal Sonic. Wendy remained trapped, but her life was spared in exchange for becoming Eggman's twelfth Egg Boss.[46][47][48]

A little while later, Sonic, Tails and Chip arrived at the settlement of Mazuri, where they learned that Axel the Water Buffalo had stolen the fourth Gaia key. While Sonic distracted the Egg Boss by challenging his enforcements to a race around the Savannah Citadel Zone, Tails and Chip managed to recover the key and gained access to the Gaia Temple's inner sanctum. Before departing, Chip regained some of his lostmemories from inside the temple.[49] Meanwhile, Sally and Rotor learned the identity of Spagonia's local guardian, Lucia, and offered to help her out with her mother's fiftieth birthday party. In gratitude of their efforts, she awarded them with the fifth Gaia key.[50]

The Freedom Fighters soon split ways again. Sonic and the gang traveled to Chun-Nan to retrieve the final key. There, they were attacked by Silver Sonic upon arriving, but were saved by the intervention of Dulcy, an old friend of theirs. The team learned from the Shijin Warriors that the Guardian Zonshen had disappeared during his usual peace offering to the resident Gaia Phoenix, who had been acting strange lately.[51] The group decided to investigate the scene but fell victim to Conquering Storm, who anticipated their move