Consummate liar

[Greta]

Your ability is top drawer--rarely does anyone lie as CONVINCINGLY or as ARTISTICALLY [as you do]. Your skill has, in short, reached the [zenith] of perfection. Indeed, your mastery of the art is so GREAT that your LYING is ALMOST ALWAYS crowned with success--and you have no trouble seducing an unwary listener into BELIEVING that you are telling [gospel truth]..(Reference: by Norman Lewis, Word Power Made Easy)