The Monsters & Creatures Compendium     Any (no source link)
The Monsters Know What They're Doing     Dungeons And Dragons original/official source
Angry Golem (web)     D&D 5e original/official source
OSE Encounter Activity Tables     Any original/official source
Pathfinder 1e Bestiary 1     Pathfinder original/official source
Pathfinder 2e Bestiary 1     Pathfinder original/official source
Mythic Adventures     Pathfinder original/official source
Monster Manual     D&D 5e original/official source
Monster Manual Expanded v1     D&D 5e original/official source
Fifth Edition Foes     D&D 5e original/official source
Tome Of Horrors 2018     D&D 5e original/official source
Kobold Press Tome Of Beasts 2     D&D 5e original/official source
Old Gus: Plantfolk, Undead, And Other Oddities     D&D 5e original/official source
Limitless Monsters     D&D 5e original/official source
Monsters Of Feyland     D&D 5e original/official source
Monster Ecology Anthology     D&D 5e (no source link)
Monster Manual     D&D 4e (no source link)
Monster Manual 2     D&D 4e (no source link)
Dungeons And Dragons Essentials: Monster Vault     D&D 4e (no source link)
D&D 2e Monstrous Manual     D&D 2e (no source link)
Scruffy Grognard's Monstrous Manual     D&D 2e (no source link)
Dragonlance Bestiary     SAGA (no source link)
Hacklopedia Of Beasts     Hackmaster original/official source
Monsters Compendium     Heroes Of Adventure (no source link)
Old World Bestiary     Warhammer original/official source
QUERP Bestiary     QUERP original/official source
Monsters And Treasure (2019)     Castles And Crusades original/official source
The Monster Overhaul     OSR (no source link)
Abnormal Undead     Any original/official source