Featuring G5 background character Bucket (placeholder name voted on through YouTube Poll) aka. Shiny Sparks (alternative placeholder name voted on through Derpibooru) inspired by their re-occurring alicorn animation errors.
Also featuring my interpretation of the Gloucester Sea Serpent based on the recent theory by Joe Nickell that the giant creature was a misidentified pod of narwhals — I obviously leaned towards a giant serpentine narwhal.
As for why I selected that specific cryptid, Bucket/ Shiny Sparks seems to have a Boston or New Jersey accent (based on a line from TYT and the opinion of Americans I've asked), so a Massachusetts mystery seemed appropriate. I did also have the Jersey Devil and Dover Demon as options in the poll I ran, but the Gloucester Sea Serpent ultimately won out.