The Evertree (Spirit Animals #7)

Conor, Abeke, Meilin and Rollan were once ordinary kids. Then they
discovered that they had spirit animals - wise and powerful partners who
granted them with amazing gifts ... and a legendary responsibility. Together,
the team has journeyed across Erdas, racing to stop a merciless foe.
They have laughed and fought together. They've won challenges and lost
friends. Some have even lost themselves.Now that journey is
about to end. They must reach a place forgotten by time and face off
against an ancient enemy breaking free from his prison. They have just
one chance to stop him ... or the whole world will shatter.