Complex sentence: As the dolphins and the Vortex do battle in the now-transformed Lunar Bay, Ecco swims to the deepest parts and infiltrates the Vortex's New Machine, then finally confronts the Vortex Queen and seemingly destroys her once and for all.
Split into simpler sentences: As the dolphins and the Vortex do battle in the now-transformed Lunar Bay, Ecco swims to the deepest parts of the bay, where the Vortex have constructed a New Machine. After a long journey, Ecco finally confronts the Vortex Queen and seemingly destroys her once and for all.