The Return of Cosmo

Plot Summary
It's been a couple of months and years ever since Cosmo's sacrifice right after defeating the Meterex, Tails perks up when he plants and waters the seed that Sonic gave him in the previous episode. When he does so, a magical green light occurs and Cosmo finally returns from it. Meanwhile, the Metal army are attacking the city town of Station Square.

Transcript
The Return of Cosmo transcript