I am Zygmunt Budge and I am the greatest potion-maker ever born. This is no empty boast -- I invented some of the Wizarding World's most powerful potions. ... I have dedicated my life to the most mysterious and misunderstood branch of magic and these pages contain the secrets of my art distilled for new generations of Hogwarts students.
-- Zygmunt Budge (BoP)
Zygmunt Budge is considered to be one of the most accomplished Potioneers the world has ever known (according to him). He is the author of The Book of Potions.
Budge was a student at Hogwarts in the 1500s and excelled at potion making. He was rather boastful and proud, and when he was told he was below the required age for the Wizarding Schools Potions Championship and could not participate, he left Hogwarts in protest and never went back. He also held a grudge against the Headmaster (unnamed) forever. Budge retired to the island of Hermetray in the Hebrides where he lived alone, working to perfect his potions. Whenever visitors from another island came his way, he used his potions skill to encourage them to leave again.
He is credited with creating a particularly potent Beautification Potion, Doxycide, Laughing Potion, a version of the Shrinking Solution, and most notably Felix Felicis (BoP).
Budge is suspected to have left a small part of his personality in his masterwork, The Book of Potions. As such, it has been classified as 'Dangerous' by the Hogwarts librarian because it has the reputation of trying to persuade those who read it to use dangerous ingredients. (BoP)
His mother did not like him, calling him "Fungus Face." Had a "giggly" great-grandmother who taught him Potion-making, handing down her recipe for Laughing Potion (BoP)
Inventor of many potions. Saw himself as a mentor to any Hogwarts student who read his Book of Potions.
Zygmunt means "victorious defender" + Budge = Norman French buge for "mouth" - the implication is that Budge is a braggert who loudly defends himself, which he does rather vociferously in the Book of Potions