Technically speaking, Blob still lives on via Allo, but since Allo is on hold for now, Google is reviving Blob as a sticker pack on Gboard and Android Messages. This new Blob pack includes stickers that were first introduced with Allo last year. It also popular emojis like the wink and grimace, and a handful of animated emojis from older Android version.
— Google (@Google) July 17, 2018
Google killed the Blob emoji last year and replaced them with a standard circular shape in order to stay inline with emojis from other operating systems. This resulted in phasing out of the Blobs and they were completely phased out right after the Oreo update. This is when Google started using Blobs to promote Allo and later, blobmoji began disappearing from other places like Google Hangouts on the web.