Laevatein is the armed device wielded by Signum, a knight of the Wolkenritter, in the Magical Girl Lyrical Nanoha series. It is an Ancient Belkan device that takes the form of a sword and is capable of transforming into a whip sword, known as Schlangeform, or a bow. Like other ancient Belkan devices, Laevatein possesses its own personality and communicates in German, though it has no programmed gender. In the film Magical Girl Lyrical Nanoha Reflection, Laevatein plays a significant combat role. During the conflict, it is overpowered by Kyrie Florian’s System Alter ability. In response, Mariel Atenza performs an urgent field upgrade, converting Laevatein into Laevatein Modified. This upgraded form is equipped with an EM Cartridge System, which enhances its power output, but the modification temporarily freezes its form‑change mechanism, preventing it from shifting into Schlangeform. Laevatein’s abilities are rooted in the Belka cartridge system, allowing it to load and fire magical cartridges for explosive increases in speed and attack power. Its relationship with Signum is one of deep trust and synergy, as the device faithfully follows its wielder’s will in battle. The upgrade in Reflection reflects the device’s adaptability and the urgency of the situation, highlighting its role as a key combat asset in the ongoing struggle against the film’s antagonists.