Unidentified Shield

Unidentified Shield is a common warrior spell card, from the Kobolds and Catacombs set.

Strategy
This spell provides a decent amount of armor as well as a small bonus. Optimizing your deck so each bonus can be used is important. Since Tower Shield +10 is always an option, it's good to plan around using your armor.

The card itself, however, is comparable to Iron Hide, which only costs one mana.

Runed Shield is effectively identical to Shieldmaiden, providing a decent body on top of armor gain.

Serrated Shield is best compared to Holy Fire, except it can be used even while at full health for no lost value. It can be used to remove a medium threat.

Spiked Shield is similar to Arcanite Reaper, paying 1 extra mana for 5 armor.

Tower Shield +10 is generally the weakest effect. While it creates a lot of armor, it's expensive and provides no tempo. You can however synergize the effect with Shield Slam or Bladed Gauntlet to kill nearly any minion.

Patch changes

 * Added.