Crocea Mors

Crocea Mors is Jaune Arc's signature weapon. Jaune states that it was passed down from his great-great-grandfather, who used it in a war.

Description
The sword itself is a simple long sword with a blue handle and a golden cross-guard. Jaune can transform the sheath into a shield for combat. The shield is a white heater shield with a gold trim, and it shows Jaune's symbol colored in gold in the center.

His explanation for the shield's transformation is that when his arm gets tired of carrying it, he can shrink it down, to which Ruby Rose replies, "Doesn't it weigh the same?," which Jaune sheepishly admits is true. It appears to deploy with significant force, enough for its tips to embed themselves in a wooden doorway in "Jaunedice."

Both the sword and shield are shown to be incredibly durable, despite apparently being forged several generations prior to the present time. The sword is sharp enough to decapitate an Ursa Major, while the shield is strong enough to take several direct blows from an Ursa, a Death Stalker, and Cardin Winchester's mace with no apparent damage.

Trivia

 * Crocea Mors is Latin for 'yellow death' and the name of Julius Caesar's sword in some legends. Appropriately, the same legends have it becoming embedded in a shield.
 * Before its name was revealed, Crocea Mors was called Sword and Shielth. Jaune's voice actor and writer of RWBY, Miles Luna, acknowledged the name created by the fans and used it during the interviews before Monty Oum decided to reveal the true name of his creation via Facebook.
 * The blade has the same design as the sword used by the male huntsman on the statue in Beacon Academy that features a huntsman, a huntress, and a Beowolf.