PixelJunk Eden
32 Achievements
21-25h
PS3
Encore: All Seeds 15
Open all seeds in garden 15, without using continues
2.0%
How to unlock the Encore: All Seeds 15 achievement in PixelJunk Eden - Definitive Guide
You will need to explore the entire stage, filling and then opening every last seed. This is harder than just grabbing the spectra, and I suggest getting this on the fifth run of garden 15, see All Spectra Found for details.
Thanks to XxDarkDiazxX for these videos: