The Oceanid Optical Compressor is adapted from the Pete Cornish OC-1 Optical Compressor, traced by Aion FX in 2019.
Cornish pedals are best known for being extremely expensive. There are two reasons for this. First, the build quality and reliability is unmatched. Second, the mysterious nature of them, partially due to the fact that the circuit is obscured and partially because of the A-list of clients such as David Gilmour and Brian May.
The OC-1 is a relatively new addition to the Cornish lineup, having been released in 2014. It notably has Paul McCartney listed as an owner.
The OC-1 is indeed an original circuit as Pete Cornish claims, and it bears the marks of careful design, without any clear comparisons to anything else out there. It uses the LDR-to-ground method of volume reduction as seen in early optical limiter circuits like the LA2A, but the methods of generating the LED control voltage from the envelope are unique, and the clean-blend circuit is a little more complex than what you normally see.
The Oceanid is a faithful reproduction of the OC-1 circuit, but with one major addition: an internal slide switch allowing the pedal to be used in true-bypass mode instead of buffered bypass. As with the Klon KTR, the buffered mode is “almost always better”, but with this feature, you can determine for yourself.