| Name | CR | Type | Environment |
| Lamhigyn | 3 | outsider (chaotic, evil, extraplanar) | any (Abyss) |
| Lamia | 6 | monstrous humanoid | temperate deserts |
| Lamia Matriarch | 8 | monstrous humanoid (shapechanger) | any land |
| Lamia-Kin, Hungerer | 15 | monstrous humanoid
| cold mountains
|
| Lamia-Kin, Kuchrima | 8 | monstrous humanoid
| any mountains
|
| Lammasu | 8 | magical beast | temperate deserts |
| Lamp Blighter | 6 | fey | temperate forests and urban |
| Lampad | 5 | fey | any underground |
| Lar | 5 | outsider (good, incorporeal, lawful, native) | any |
| Larabay | 11 | fey (shapechanger) | temperate or warm coastlines or forests |
| Larva of the Outer Gods | 15 | aberration | any |
| Lashunta | 1/2 | humanoid (lashunta) | any (Castrovel) |
| Lava Child | 3 | monstrous humanoid (earth, fire) | volcanic underground |
| Lava Lurker | 9 | outsider (elemental, extraplanar, fire) | any volcano or underground |
| Leaf Ray | 1 | plant | temperate or warm forests |
| Leech, Giant Leech | 2 | vermin (aquatic) | temperate or warm marshes |
| Leech, Leech Swarm | 4 | vermin (aquatic, swarm) | temperate or warm marshes |
| Leechroot | 4 | undead | any forests |
| Leng Hound | 10 | aberration (extraplanar) | any |
| Leng Spider | 14 | magical beast (extraplanar) | any |
| Leprechaun | 2 | fey | temperate forests |
| Leshy, Cactus Leshy | 2 | plant (leshy) | warm deserts |
| Leshy, Flytrap Leshy | 4 | plant (leshy, shapechanger) | warm marshes
or wetlands |
| Leshy, Fungus Leshy | 2 | plant (leshy, shapechanger) | any swamp or underground |
| Leshy, Gourd Leshy | 1 | plant (leshy, shapechanger) | any hills or plains |
| Leshy, Leaf Leshy | 1/2 | plant (leshy, shapechanger) | any forest or hill |
| Leshy, Lichen Leshy | 3 | plant (leshy, shapechanger) | any hills or mountains |
| Leshy, Lotus Leshy | 5 | plant (leshy, shapechanger) | warm lakes or ponds |
| Leshy, Seaweed Leshy | 3 | plant (aquatic, leshy, shapechanger) | any ocean or coastline |
| Leshy, Snapdragon Leshy | 4 | plant (leshy, shapechanger) | temperate hills or urban |
| Leshy, Sunflower Leshy | 1 | plant (leshy) | any warm plains or hills |
| Leucrotta | 5 | magical beast | temperate or tropical forests or hills |
| Leviathan | 30 | magical beast (water) | any oceans (First World) |
| Liavaran Dreamer | 8 | aberration | any sky |
| Lich | 12 | undead (augmented humanoid) | any |
| Lich Newt | 1/4 | animal (aquatic) | temperate marshes or plains |
| Lich, Demilich | 14 | undead | any |
| Lich, Forsaken Lich | 12 | undead (augmented humanoid) | — |
| Lich, Psychic Lich | 12 | undead (augmented humanoid) | any |
| Liminal Sprite | 2 | fey | any urban |
| Linnorm, Cairn Linnorm | 18 | dragon | cold hills |
| Linnorm, Crag Linnorm | 14 | dragon | cold hills |
| Linnorm, Fjord Linnorm | 16 | dragon (aquatic) | cold mountainous coastlines |
| Linnorm, Gare Linnorm | 15 | dragon (aquatic) | cold rivers |
| Linnorm, Ice Linnorm | 17 | dragon | cold hills and mountains |
| Linnorm, Sea Linnorm | 22 | dragon (aquatic) | cold oceans |
| Linnorm, Taiga Linnorm | 19 | dragon | cold forests |
| Linnorm, Tarn Linnorm | 20 | dragon (aquatic) | cold lakes and swamps |
| Linnorm, Tor Linnorm | 21 | dragon | cold volcanic mountains |
| Lion | 3 | animal | warm plains |
| Lion Alebrije | 5 | magical beast (extraplanar) | any (Dimension of Dreams) |
| Lion, Dire Lion (Spotted Lion) | 5 | animal | warm plains or hills |
| Litanu | 11 | undead (aquatic) | any oceans |
| Living Cave Painting | 4 | aberration | any underground |
| Living Doldrums | 12 | outsider (air, elemental, extraplanar) | any air (Plane of Air) |
| Living Effigy | 8 | construct | any |
| Living Mirage | 9 | ooze | any deserts or oceans |
| Living Rune | 13 | aberration | any |
| Living Sandstorm, Living Sandstorm (Humanoid) | 11 | outsider (earth, elemental) | any desert (Plane of Earth) |
| Living Sandstorm, Living Sandstorm (Sandstorm) | 11 | outsider (earth, elemental, swarm) | any desert (Plane of Earth) |
| Living Topiary | 4 | plant | any land |
| Living Wall | 4 | construct | any ruins or underground |
| Lizard, Giant Chameleon | 3 | animal | warm forests and mountains |
| Lizard, Giant Frilled Lizard | 5 | animal | warm forest, plains, or hills |
| Lizard, Giant Gecko | 1 | animal | any warm forest or mountains |
| Lizard, Giant Gecko | 1 | animal | warm forests or mountains |
| Lizard, Monitor Lizard | 2 | animal | warm forests or plains |
| Lizardfolk | 1 | humanoid (reptilian) | temperate swamps |
| Lizardfolk, Lizard Scion | 5 | humanoid (reptilian) | temperate swamps |
| Lizardfolk, Lizardfolk Berserker | 5 | humanoid (reptilian) | temperate swamps |
| Lizardfolk, Lizardfolk Champion | 10 | humanoid (reptilian) | temperate swamps |
| Lizardfolk, Lizardfolk Clutch Mother | 13 | humanoid (reptilian) | temperate swamps |
| Lizardfolk, Lizardfolk Rattler | 5 | humanoid (reptilian) | temperate swamps |
| Lizardfolk, Lizardfolk Sorcerer | 12 | humanoid (reptilian) | temperate swamps |
| Lizardfolk, Lizardfolk Stalker | 3 | humanoid (reptilian) | temperate swamps |
| Lizardfolk, Lizardfolk Swamp Lurker | 8 | humanoid (reptilian) | temperate swamps |
| Lizardfolk, Lizardfolk Vanguard | 2 | humanoid (reptilian) | temperate swamps |
| Llama | 1/2 | animal | cold or temperate hills or mountains |
| Llorona | 11 | undead (incorporeal) | any shorelines or swamps |
| Locathah | 1/2 | humanoid (aquatic) | temperate or warm aquatic |
| Locust, Giant Locust | 3 | vermin | temperate or warm deserts or plains |
| Locust, Locust Swarm | 2 | vermin (swarm) | temperate or warm deserts or plains |
| Locust, Plague Locust Swarm | 8 | vermin (swarm) | warm deserts or plains |
| Lorelei | 12 | aberration (aquatic) | any coastlines |
| Lotus Tree | 20 | plant | any coastlines or forests |
| Lovelorn | 4 | undead | any |
| Lukwata | 11 | magical beast (aquatic) | warm rivers, lakes, and swamps |
| Lunarma | 6 | aberration | any underground |
| Lurker in Light | 5 | fey (extraplanar) | any land (extraplanar) |
| Lurking Ray, Executioner's Hood | 2 | aberration | any underground |
| Lurking Ray, Lurker Above | 7 | aberration | any underground |
| Lurking Ray, Trapper | 8 | aberration | any underground |
| Lusca | 17 | magical beast (aquatic) | warm oceans |
| Lycanthrope, Silverblood Lycanthrope (Human Form) | 5 | humanoid (human, shapechanger) | Any land |
| Lycanthrope, Silverblood Werewolf (Hybrid Form) | 5 | humanoid (human, shapechanger) | Any land |
| Lycanthrope, Werebat (Human Form) | 3 | humanoid (human, shapechanger) | temperate forests or hills |
| Lycanthrope, Werebat (Hybrid Form) | 3 | humanoid (human, shapechanger) | — |
| Lycanthrope, Werebear (Human Form) | 4 | humanoid (human, shapechanger) | any forests |
| Lycanthrope, Werebear (Hybrid Form) | 4 | humanoid (human, shapechanger) | any forests |
| Lycanthrope, Wereboar (Human Form) | 2 | humanoid (human, shapechanger) | any forests or plains |
| Lycanthrope, Wereboar (Hybrid Form) | 2 | humanoid (human, shapechanger) | any forests or plains |
| Lycanthrope, Werecrocodile (Human Form) | 3 | humanoid (human, shapechanger) | warm rivers or marshes |
| Lycanthrope, Werecrocodile (Hybrid Form) | 3 | humanoid (human, shapechanger) | — |
| Lycanthrope, Wereraptor (Human Form) | 3 | humanoid (human, shapechanger) | temperate forests and mountains |
| Lycanthrope, Wereraptor (Hybrid Form) | 3 | humanoid (human, shapechanger) | temperate forests and mountains |
| Lycanthrope, Wererat (Human Form) | 2 | humanoid (human, shapechanger) | any urban |
| Lycanthrope, Wererat (Hybrid Form) | 2 | humanoid (human, shapechanger) | any urban |
| Lycanthrope, Wereshark (Human Form) | 3 | humanoid (human, shapechanger) | any oceans or coastlines |
| Lycanthrope, Wereshark (Hybrid Form) | 3 | humanoid (human, shapechanger) | — |
| Lycanthrope, Weretiger (Human Form) | 4 | humanoid (human, shapechanger) | any plains or swamps |
| Lycanthrope, Weretiger (Hybrid Form) | 4 | humanoid (human, shapechanger) | any plains or swamps |
| Lycanthrope, Werewolf (Human Form) | 2 | humanoid (human, shapechanger) | any land |
| Lycanthrope, Werewolf (Hybrid Form) | 2 | humanoid (human, shapechanger) | any land |
| Lythirium | 11 | plant | cold or temperate forests |