Wonderful term. Firstly, where do you go to find an assembly of carvers? A school of butchery surely, or a trade fair for knives. Secondly, ’embruing’ sent me to the dictionary to learn that it stems from ’embrue’, an alternative spelling of ‘imbrue’ which means ‘to stain in or with blood, slaughter, etc’.
(That ‘etc’ is concerning.)
From Old French ’embruer’, to bedaub, bedabble, another two neglected words.