Here lots of different creatures (aka "monsters") are described.
Creatures marked with "*" here are described with different types below.
And partly the file "Another_List_of_Monsters" explains
the same creatures, but also others.

Categories:
ANIMAL              DEMIHUMAN           HUMANOID            LESSER ANIMAL
MAGICAL CREATURE    UNDEAD              SEA ANIMAL

ANIMAL:
Bear*               Bird*               Cat                 Cat, Giant*
Dog                 Elephant            Horse*              Insect*
Mammal*             Mammal, Herd*       Mammal, Small*      Unicorn
Wolf

DEMIHUMAN:
Brownie             Centaur             Dryad               Dwarf
Gnome               Halfling            Human*              Kobold
Leprechaun          Nymph               Satyr               Sprite

HUMANOID:
Bugbear             Cyclops             Giant, Fire         Giant, Frost
Giant, Hill         Giant, Stone        Giant, Storm        Goblin
Half-Ogre           Half-Orc            Hobgoblin           Imp
Lizard Man          Ogre                Orc                 Troll
Troll, Desert       Troll, Giant        Troll, Ice          Yeti

LESSER ANIMAL:
Bat                 Bat, Large          Beetle, Giant       Centipede, Giant
Crocodile           Frog, Giant         Leech, Giant        Rat
Rat, Giant          Scorpion, Giant     Slug, Giant         Snake
Spider*             Worm, Purple        Worm, Giant-Blood

MAGICAL:
Basilisk            Beholder            Djinni              Dragon
Gargoyle            Gremlin             Harpy               Manticore
Medusa              Minotaur            Pegasus             Phoenix
Spectre             Sphinx              Will O'Wisp         Wyvern

UNDEAD:
Banshee             Death Knight        Ghost               Ghoul
Golem               Haunt               Lich                Mummy
Skeleton            Skeleton, Giant     Skeleton Warrior    Phantom
Vampire             Werewolf            Zombie              Zombie Lord
Zombie, Sea

SEA:
Crab, Giant         Fish, Giant*        Dolphin             Kraken
Leviathan           Lurker              Octopus, Giant      Squid, Giant
Whale               Whale, Killer