Spire Shield
Spire Shield is an Act 4 elite enemy fought alongside Spire Spear in the Spire Shield and Spire Spear encounter. It has 110/120 HP and uses Bash (hits for significant damage), Fortify (gains a large amount of Block), and Smash (deals heavy damage and removes one of the player's relics). The relic removal is one of the most devastating effects in the game.
Spire Shield must be killed quickly to prevent it from using Smash and removing a key relic. Prioritizing Spire Shield before Spire Spear is often recommended, though Fortify can make it difficult to burst down. Having strong burst damage and timing kills to avoid the Smash turn is essential. The relic it removes is chosen randomly from your current relic pool, making any valuable relic a potential target.