Bundle of Holding has three bundles with Champions, Hero System, and Magazines totally about $75. Pretty much I didn't have all this in PDF except for Digital Hero. Also don't have Mythic Greece at all.

HERO-001      1981        PDF     Champions: The Superhero Role Playing Game
HERO-001      1982 Rev    PDF     Champions (Revised, 2E)
HERO-001      1984 6P     PDF     Champions 3E
HERO-002      1981        PDF     Enemies
HERO-002      1982 Rev,2P PDF     Enemies (Revised)
HERO-003      1981        PDF     The Island of Dr Destroyer (Adventure 1)
HERO-004      1981        PDF     Escape from Stronghold (Adventure 2)
HERO-005      1981        PDF     Gamemaster's Screen for Champions
HERO-006      1982        PDF     Enemies II
HERO-007      1983        PDF     Estionage! The Secret Agent Role Playing Game
HERO-008      1982        PDF     Champions II
HERO-008      1982 Rev    PDF     Champions II (Revised)
HERO-009      1983        PDF     Deathstroke (Adventure 3)
HERO-010      1983        PDF     Border Crossing (for Espionage!)
HERO-011      1984        PDF     The Great Super Villain Contest
HERO-012      1983        PDF     The Circle and M.E.T.E. (Organizations 1)
HERO-013      1984 2P     PDF     Justice Inc.
HERO-014      1984 1P     PDF     Trail of the Gold Spike (Justice Inc Adventure #1)
HERO-015      1984 2P     PDF     Champions III
HERO-016      1984 1P     PDF     Enemies III
HERO-017      1985 1P     PDF     Danger International
HERO-018      1985        PDF     Primus and Demon (Organizations 2)
HERO-019      1985        PDF     Champions Gamemaster's Screen
HERO-020      1985 1P     PDF     Lands of Mystery (for Justice Inc)
HERO-021      1985 1P     PDF     The Blood and Dr McQuark (Organizations 3)
HERO-022      1986 1P     PDF     Super Agents (Campaign Supplement)
HERO-023      1986 2P     PDF     Gadgets!
HERO-024      1985 1P     PDF     Fantasy Hero
HERO-025      1986 1P     PDF     The Hero System Bestiary
HERO-026      1986 1P     PDF     The Coriolis Effect (Adventure 5)
HERO-027      1986 1P     PDF     Robot Warriors
HERO-028      1986 1P     PDF     S.H.A.D.O.W. Over Scotland (for Danger International)
HERO-029      1987 1P     PDF     Magic Items (for Fantasy Hero)
HERO-030      1988 1P     PDF     Enemies: The International File
HERO-031      1987 1P     PDF     Wrath of the Seven Horsemen (Adventure)
HERO-034      1988 1P     PDF     Target Hero (Adventure)
HERO-035      1988 1P     PDF     Robot Gladiators (for Robot Warriors)
HERO-036      1988 1P     PDF     Enemies: Villany Unbound
HERO-038      1987 1P     PDF     Voice of Doom (Adventure)
HERO-039      1988 1P     PDF     Red Doom (Organizations)
HERO-040      1988 1P     PDF     Scourge from the Deep (Campaign)
HERO-041      1989 1P     PDF     The Spell Book (for Fantasy Hero)
HERO-042      1988 1P     PDF     Strike Force (Campaign Sourcebook)
HERO-044      1988 1P     PDF     To Serve and Protect (Adventure)
HERO-046      1989 1P     PDF     C.L.O.W.N. (Organizations)
HERO-047      1989 1P     PDF     Neutral Ground (Adventure)
HERO-048      1989 1P     PDF     Atlas Unleashed (Adventure)
HERO-050      1989 1P     PDF     Star Hero

Adventurers Club #1-27 (for Hero 2E to 4E)
Digital Hero #1-47 (for Hero 5E)
Haymaker Archives v1-7 (a Hero System APA Zine for Hero 4E to 6E?)

Chaosium

CHA-2403      1984        PDF     Trouble for HAVOC

Firebird Limited

FBL-1001      1983        PDF     The Armory v1 (for Espionage!)
FBL-1002      1985        PDF     The Golden Age of Champions
FBL-1003      1986        PDF     Here There Be Tigers (for Danger International)

Flying Buffalo

FBI-3101      1983 2019P  PDF     The Adventure of the Jade Jaguar (for Espionage!)
FBI-3301      1983 1P     PDF     Stormhaven (for Espionage!)
FBI-3304      1992 1P     PDF     Mugshots 2: Taking Care of Business (for Espionage!)

I.C.E.

ICE-1020      1988 1E     PDF     Mythic Greece: The Age of Heroes (for Fantasy Hero)

Steve Jackson Games

SJG-7107      1983        PDF     Autoduel Champions