The Monsters Know What They're Doing 2 (moar)     Dungeons And Dragons (no source link)
Angry Golem (web)     D&D 5e original/official source
Pathfinder 1e Bestiary 1     Pathfinder original/official source
Pathfinder 2e Bestiary 1     Pathfinder original/official source
All Sorts Of Critters (web)     Pathfinder original/official source
Fifth Edition Foes     D&D 5e original/official source
Tome Of Horrors 2020     D&D 5e original/official source
Untamed Wilds     D&D 5e original/official source
Volo's Guide To Monsters     D&D 5e original/official source
Monster Manual 3     D&D 4e (no source link)
Encyclopedia Of Lifeforms Mundane And Magical     D&D 3e (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)