| Name | Map Tool Token Link | Family | Type | Size | CR |
|---|---|---|---|---|---|
| Sahuagin | |
Sahuagin | Monstrous humanoid | Medium | 2 |
| Salamander | RPTok | Salamander | Outsider | Medium | 6 |
| Satyr | |
Satyr | Fey | Medium | 4 |
| Giant Scorpion | RPTok | Scorpion | Vermin | Large | 3 |
| Sea Hag | |
Sea Hag | Monstrous humanoid | Medium | 4 |
| Sea Serpent | RPTok | Sea Serpent | Magical beast | Gargantuan | 12 |
| Shadow | |
Shadow | Undead | Medium | 3 |
| Greater Shadow | |
Shadow | Undead | Medium | 8 |
| Shadow Mastiff | |
Shadow Mastiff | Outsider | Medium | 5 |
| Shambling Mound | |
Shambling Mound | Plant | Large | 6 |
| Dire Shark (Megalodon) | RPTok | Shark | Animal | Gargantuan | 9 |
| Shark | RPTok | Shark | Animal | Large | 2 |
| Shocker Lizard | |
Shocker Lizard | Magical beast | Small | 2 |
| Shoggoth | RPTok | Shoggoth | Ooze | Huge | 19 |
| Skeletal Champion | RPTok | Skeletal Champion | Undead | Medium | 2 |
| Human Skeleton | RPTok | Skeleton | Undead | Medium | 1/3 |
| Skum (Ulat-Kini) | RPTok | Skum | Monstrous humanoid | Medium | 2 |
| Giant Slug | RPTok | Slug | Vermin | Huge | 8 |
| Constrictor Snake | |
Snake | Animal | Medium | 2 |
| Venomous Snake | RPTok | Snake | Animal | Medium | 1 |
| Spectre | |
Spectre | Undead | Medium | 7 |
| Sphinx (Gynosphinx) | RPTok | Sphinx | Magical beast | Large | 8 |
| Giant Spider | RPTok | Spider | Vermin | Medium | 1 |
| Giant Squid | RPTok | Squid | Animal | Huge | 9 |
| Squid | RPTok | Squid | Animal | Medium | 1 |
| Stirge | |
Stirge | Magical beast | Tiny | 1/2 |
| Svirfneblin | RPTok | Svirfneblin | Humanoid | Small | 1 |