Ulrich's Saber, called a Katana in Japanese, is his primary weapon in Lyoko. He uses it to deflect enemy blows and cut them in half. Coupled with his super sprint ability, the monsters he faces usually last only seconds. The weakness of his sword is that it's a short range weapon, he might not be able to defeat monsters with their Eye of XANA far off the ground. Ulrich can also throw his saber. The most recent throw was in XANA's Kiss, when he threw it like a boomerang to sever the slimy tentacles of the Scyphozoa. It is shown that the saber can be devirtualized by a laser in The Pretender, in which the saber was devirtualized by a Hornet. If this happens, the person operating the supercomputer must revirtualize it.
On Earth, Ulrich practices Pencak Silat, a martial art commonly involving the use of swords and similar weapons. He used the sword that came with samurai armor, an Ishiyama heirloom, in A Bad Turn to fight off materialized monsters. This sword bears a remarkable resemblance to the Saber he uses in Lyoko; however, it does not glow blue and is not laser-absorbant, but it does deflect lasers.
In Franz Hopper, XANA-Franz Hopper modified Ulrich's katana. The upgraded katana could be charged up to fire an energy wave that could destroy multiple enemies. The modifications were lost when XANA-Franz Hopper betrayed Team Lyoko. A similar event happens in Nobody in Particular when Ulrich's possessed body used a long-range attack to try to destroy The Core of Lyoko as seen in the picture on the right.
- Whenever someone possessed by XANA grabs Ulrich's sabers it turns red, like in Skidbladnir (William) and in Wrong Exposure (Aelita). This also happens if Ulrich happens to be the form of a polymorphic clone on Lyoko, like in Revelation. It is unsure whether Ulrich can devirtualize himself with his own saber, but this is the closest this has ever happened.
- In Garage Kids, Ulrich's saber is made out of binary code and must be "charged" by Jeremie.
- So far, it is the only weapon to match the Zweihander, since Ulrich can defend himself from the Zweihander using his saber(s).