Monstrosities     Swords & Wizardry 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 2     Pathfinder original/official source
Tome Of Horrors 2018     D&D 5e original/official source
Critter Cache: Animals And Beasts     D&D 4e original/official source