You can follow his spiralling, foam-flecked descent into madness here.
Part 0: Prelude and Rules for Mythus Drinking Game
MYTHUS PRIME
In which co-author Dave Newton expresses his love for Runequest in the form of a fanhack of Advanced Mythus.
Part 1: Introductory Guff
Part 2: Creating a Precious Snowflake
Part 2.1: Example Character
Part 3: Magickqkc, Fighting and Being a Good Player
Part 4: Upgrading to Advanced Mythus, the GM's Section + sample adventure
ADVANCED MYTHUS
Full fat Mythus, as vouchsafed unto the world by EGG.
(Here be Slivey Toves and Snarks and 'orrible 'orrible Grues.)
Part 5: Advanced Chargen 1: Social Class and Vocation
Part 6: Advanced Chargen 2: K/S Area Bundles
Part 7: Advanced Chargen 3: Additional skills + General character info
Part 8: Advanced Chargen 4: Resources and Contacts
Part 9: Core Game Systems, aka Da Roolz
Part 10: K/S Area Descriptions 1: Mental skills A-F
Part 11: K/S Area Descriptions 2: Mental skills G-Z
Part 12: K/S Area Descriptions 3: Physical skills A-H
Part 13: K/S Area Descriptions 4: Physical skills J-Z
Part 14: K/S Area Descriptions 5: Spirit skills A-M
Part 15: K/S Area Descriptions 6: Spirit skills M-Z
Part 16: Using K/S Areas for Economic Gain
Interlude: Mystic Masters Magazine, or "No, Gary Wasn't Kidding"
Part 17: Combat 1: Initiative, Avoidance, and Mental, Spiritual & Heka Attacks
Part 18: Combat 2: Physical Combat, Non-Lethal
Part 19: Combat 3: Physical Combat, Lethal
Part 20: Combat 4: Weapons and Armour
Part 21: Combat 5: Other Sources of Agony + Healing Rules
Interlude: the art of Mythus Chapter 12
Part 22: Heka and Magick 1: Heka, the Getting and Having
Part 23: Heka and Magick 2: Dweomercraeft, Priestcraeft
Part 24: Heka and Magick 3: Apotropaism, Astrology
Part 25: Heka and Magick 4: Herbalism, Mysticism
Part 26: The Campaign and Gamesmastering
Part 27: stuff
Part 28: More stuff
Part 29: Stuff galore!
Part 30: Stuff overwhelming
Part 31: Oh no! There's stuff everywhere!!!
Part n+1: Sweet merciful lord, does it never end?!
Fellow Carriers of the Infection
Mike's Mythus Page - fan page with lotsa content.
Mad Irishman's Mythus page - includes a Mythus-ised Sinister Secret of Saltmarsh adventure.
Jon Simpson's Mythus page - includes .ods and .xls Mythus character generators.
Dragonsfoot Mythus Thread - The eremites of Old School make the case for Mythus as prelude to D&D 3E...
K&KA Dangerous Dungeons - The cenobites of Old School kitbash OSRIC and DJ:M together.
GaryCon Mythus Thread - The stylites of Old School reminisce about the great times had with this "smooth [...] realistic [...] intuitive [...] balanced" system
The Great Mythus Swindle by Sirlarkin - complete with "ignore stuff" pro-tip from no less a figure than Dave Newton.
RPG.net review of Mythus - Mardius Bredsdorff opines. RPG.net, so, yeah, pinch of salt.
The Infamous Mythus Suit - In which TSR Corporate and their pet lawtrolls (the unimprovably named Wanke, Schlitter and Suri) display the scale of their intellectual and moral bankruptcy.
I Was a Gen Con Spy for TSR - Colin McComb reminisces about undercover operations against EGG over at Kobold Quarterly.