The Cobalt Shield is an accessory that grants the player immunity from knockback when equipped. It also provides 1 defense, which stacks with defense from Obsidian Skulls and Shackles. It is obtained only from Gold Chests found in the Dungeon, or by opening Golden Lock Boxes found in Dungeon Crates.
- The protection against knockback is particularly valuable when the player is likely to come into frequent contact with enemies and environmental hazards, including but not limited to: lava in the Underworld, Bats in the Underground, and map-generated traps in the Cavern and Dungeon.
- The knockback immunity is also of particular use when the player is on the move. For instance, farming for Fallen Stars while equipping the Hermes Boots will allow no speed interruptions caused by damage, and traversing through a chasm will prevent deadly fall damage from possible knockback caused by contact from the commonly encountered Eater of Souls.
- Desktop 1.1: Can now be combined with the Obsidian Skull to craft the Obsidian Shield.
- Console 1.06: Sprites and graphics updated to match Desktop 1.2.3.
- Mobile 1.1.5536: Can now be combined with the Obsidian Skull to craft the Obsidian Shield.
- 3DS-Release: Introduced with stats from Desktop 1.1 and sprites and graphics from Desktop 1.2.3.