The Monsters Know What They're Doing Dungeons And Dragons original/official source
Atlas Animalia Any 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
Tome Of Horrors Complete Pathfinder original/official source
All Sorts Of Critters (web) Pathfinder original/official source
Exotic Encounters Pathfinder original/official source
Monster Manual D&D 5e original/official source
Flee, Mortals D&D 5e (no source link)
Monster Ecology Anthology D&D 5e (no source link)
Monster Manual D&D 4e (no source link)
Dungeons And Dragons Essentials: Monster Vault D&D 4e (no source link)
Scruffy Grognard's Monstrous Manual D&D 2e (no source link)
AD&D Monster Manual AD&D 1e (no source link)
13th Age Bestiary 13th Age original/official source
Dragonlance Bestiary SAGA (no source link)
Hacklopedia Of Beasts Hackmaster original/official source
Monsters Compendium Heroes Of Adventure (no source link)
Monster Guide World Of Warcraft RPG original/official source
Godforsaken Cypher System (no source link)
QUERP Bestiary QUERP original/official source
Fantasy Age Bestiary Fantasy Age original/official source
Mystara Adversary Compendium I Dragon Age original/official source
The Monster Overhaul OSR (no source link)
Iron Falcon Handbook Of Monsters OSR (no source link)
Creatures Of Barsaive Earthdawn original/official source
Lairs And Encounters Adventurer, Conqueror, King (no source link)
Baby Bestiary 1 Any original/official source