Shield

The shield is a tool that can be equipped by all human characters, including enemies and companions. But the shield item drop can only be picked up by the player (and in theory by the bandit boss). Enemies spawn with shields pre-equipped and companions can only get them from upgrades. When equipped the shield is visible and rotates in the direction the weapon is facing. It will block ranged and melee attacks but does not guarantee full protection, because the back of the character is still exposed and the shield itself might also be penetrated. Shields do not offer protection against explosions or ram attacks.

Shields can be found in shield and locked crates and dropped by certain enemies and all bosses. It will never drop from regular containers. If an enemy with a shield is killed before their shield is destroyed there is a small change a shield item is dropped. If the shield of a shielded enemy is destroyed they will never drop a shield item.

For players
There is no limit to how many shields can be in the player's inventory. But there is always only one shield equipped at once. It acts as a throwaway bonus health, similar to armor in other roguelike games, but only for the front of the player. The back of the player is still exposed, so it is important to aim towards whatever you want to be protected from.

A shield, just like a heart, has two health points and can be partially damaged. After absorbing 2 or more damage the shield will break and possible be penetrated, hitting the player with reduced damage afterwards. An attack with high penetration power (Rifles) might deal significant damage after breaking the shield, while attacks with low penetration power (shotguns or bows) might not be able to deal any damage after breaking the shield, even if their attack usually deals more than two damage. Therefore the shield armor system is very complex and difficult to predict. But it is always better to have a shield than to not have a shield.

When a shield breaks and there are spare shields in the player's inventory the next shield will be equipped shortly afterwards, but there is a 1 second delay between the first shield breaking and the new shield being equipped.

Melee attacks will be completely absorbed by shields if coming from the front.

In theory player-shields can also be penetrated without breaking, but because enemies have reduced penetration power all weapons that could penetrate the shield will usually damage the shield to the point of breaking as well.

For enemies
Enemies can only get a shield when initially spawned. Either by becoming an elite or because their enemy type always has a shield equipped.

Shields on enemies always have much more health than player-shields but can be destroyed if enough damage was dealt to them. Shell weapons deal bonus damage against shields.

Some weapons are able to penetrate shields, especially on low-level enemies, and hit the enemy with reduced damage right through their shield without breaking it.

Because shields reduce the agility of enemies it is possible to get behind an enemy with a shield and attack their exposed back, where the shield will offer no protection.

If a non-elite enemy has a shield equipped when killed a shield item might get dropped.

For companions
Shields on companions act just like shields on enemies.

Companions cannot equip shields on their own, they can only receive them through the Companion Armor upgrade.

The companion shield has 50 HP (25 × ) by default and protects better against penetration than even the best elite shield. With the Reinforced Shields upgrade the health of existing shields on companions is increased by additional 12.5 HP, resulting in a maximum health of 75 HP (50 × ).

This makes companions basically immune to attacks, at least from the front. But there is no way to restore the shield's health.