 Rusty | 3 | 38/128 |
| Rusty | 10 | 23/128 |
| Rusty | 5 | 9/128 |
| Rusty | 15 | 4/128 |
| Rusty | 25 | 1/128 |
| Rusty | 3 | Always |
| Rusty chest | 100–200 | 20/60 |
| Rusty scimitar | 1,500–1,999 | 1/100 |
| Rusty sword (Tindel Marchant) | 1,500–1,999 | 1/100 |
 Salarin the twisted | 3 | 5/128 |
| Salarin the twisted | 24 | 3/128 |
| Salarin the twisted | 10 | 3/128 |
 Salvager (1) | 3 | Always |
 Sand Crab (Active) | 4 | 29/128 |
| Sand Crab (Active) | 8 | 6/128 |
| Sand Crab (Active) | 36 | 8/128 |
 Sarachnis | 17,000–25,000 | 6/100 |
 Saradomin wizard | 77 | 17/128 |
| Saradomin wizard | 89 | 25/128 |
| Saradomin wizard | 240 | 3/128 |
| Sarcophagus (Ancient Pyramid) | 26 | Rare |
| Sarcophagus (Ancient Pyramid) | 1,000 | Rare |
| Sarcophagus (Klenter's Pyramid) | — | Rare |
| Sarcophagus (Klenter's Pyramid) | 1,000 | Rare |
 Sassilik | 40 | Always |
 Scarab Mage (Level 66 (Contact!)) | 2,000–3,000 | 32/128 |
| Scarab Mage (Level 66 (Contact!)) | 3,000 | 1/780.19 |
 Scorpia | 25,002–34,962 | 7/128 |
 Screaming banshee | 13 | 10/128, 3 rolls |
| Screaming banshee | 26 | 8/128, 3 rolls |
| Screaming banshee | 35 | 8/128, 3 rolls |
 Screaming twisted banshee | 130 | 9/128, 3 rolls |
| Screaming twisted banshee | 35 | 7/128, 3 rolls |
| Screaming twisted banshee | 260 | 7/128, 3 rolls |
| Scurrius (MVP) | 1,000–9,000 | 6/100 |
 Sea Snake Hatchling | 44 | 60/128 |
| Sea Snake Hatchling | 32 | 11/128 |
| Sea Snake Hatchling | 24 | 9/128 |
| Sea Snake Hatchling | 23 | 7/128 |
 Sea Snake Young | 44 | 60/128 |
| Sea Snake Young | 32 | 11/128 |
| Sea Snake Young | 24 | 9/128 |
| Sea Snake Young | 23 | 7/128 |
 Sergeant | 1 | 19/128 |
| Sergeant | 7 | 16/128 |
| Sergeant | 12 | 9/128 |
| Sergeant | 4 | 8/128 |
| Sergeant | 25 | 4/128 |