Shield of Sand

Whenever Gaara is about to come to harm, a shield of sand will automatically surround and protect him. The sand will react regardless of Gaara's will, even protecting him from self-inflicted injuries, due to One-Tailed Shukaku's desire to survive. The shield is capable of withstanding considerably strong attacks and projectiles, and can be hardened to a point where it's stronger than steel.

It can be defeated by avoiding it completely with extremely high-speed attacks, such as Rock Lee's superspeed taijutsu or merely overcoming the shield with incredible brute force, like Sasuke's Chidori.