| Name ▲ | Type | CR | Version | Book |
|---|---|---|---|---|
| Iron Golem | Construct | 16 | 2014/2024 | Multiple Books (MM, XMM) |
| Ironscale Hydra | Monstrosity | 12 | 2014 | Mythic Odysseys of Theros |
| Irvan Wastewalker (Tier 1) | Humanoid | 3 | 2014 | Critical Role: Call of the Netherdeep |
| Irvan Wastewalker (Tier 2) | Humanoid | 5 | 2014 | Critical Role: Call of the Netherdeep |
| Irvan Wastewalker (Tier 3) | Humanoid | 8 | 2014 | Critical Role: Call of the Netherdeep |
| Isabela Folcarae | Humanoid | 2 | 2024 | Quests from the Infinite Staircase |
| Isarr Kronenstrom | Humanoid | 8 | 2014 | Icewind Dale: Rime of the Frostmaiden |
| Isendraug | Dragon | 13 | 2014 | Storm King's Thunder |
| Ishel | Humanoid | 1/2 | 2014 | Explorer's Guide to Wildemount |
| Ishvern | Humanoid | 1/2 | 2014 | Dragonlance: Shadow of the Dragon Queen |