- "AHAHAHAHAHA! Do you hear the sound of thunder?!"
- — Richtofen when killing Zombies with the KT-4.
The KT-4, also known as the Kusanagi-no-Tsurugi, is a buildable Wonder Weapon that appears in the map Zetsubou No Shima. It's capable of releasing a green liquid that makes spore bags grow on the Zombies' bodies and makes them explode. The Thrashers' spore bags will explode, making them easier to kill, whilst the Spiders instantly explode upon being affected by the weapon.
For a better and more lethal shot, the player has to hold down the trigger. If done so, the liquid will stay on the floor, and affect any enemy that goes over it, much like the Sliquifier from Die Rise.
In order to acquire the KT-4, the player needs to acquire three parts:
- Flower Plant - In the Bunker, open the door to Mule Kick, then swim in the tunnel next to it. Swim further inside the path with blue 115 rocks all around. At the end of the path, the plant can be seen and picked up.
- Spider Venom - During a Spider round, a Spider must be lured to Lab A, then lower the cage in the Lab. Lure the Spider into the cage, then raise the cage up. Press the panel next to the cage, and the spider will be extracted of its venom. The venom can then be picked up.
- Green Vial - Kill a zombie with a green glow. This zombie will be a scientist model, and spawns around Lab B, after the main power switch has been activated.
After collecting all three parts, head down to the Bunker, where the player can find a table to put all three parts in. Afterwards, the KT-4 can be picked up. After the initial build, the KT-4 can be acquired from the Mystery Box by all players.
The KT-4 can be upgraded to the Masamune, a more powerful variant that has a larger chain effect. In order to upgrade, the players would need to acquire "Rainbow water" for the Bucket, seeds, the Shield and the Skull of Nan Sapwe. As with the initial build, players need three parts:
- Giant Spider Tooth - Use the KT-4 to gain access to the Giant Spider's lair and fight it. After killing it, approach the spider, and the player can acquire one of its teeth, as well as free Widow's Wine.
- 115 Vial - Electrify the Shield, by completing all trials at the Skull altar. Head to Lab B and using the electrified shield, melee the control panel of the cage. Use the cage to lower down into an underground area, where a corpse with a 115 vial can be seen. Grab the vial.
- Underwater Plant - In the same area where the original plant part can be picked up, there is a secret area (on the right wall across from the spore) that can be revealed using the Skull of Nan Sapwe's "Mesmerize." Plant a seed in this area and water it consecutively for three rounds using the "Rainbow Water" acquired from the sewer pipe. Afterwards, the plant can be harvested. Note that the wall cannot be opened until the player has mesmerized the blueprints on the wall and the door to the elevator shaft's generator.
After all three parts are gathered, put them on a table next to the KT-4 table, and the KT-4 will then be upgraded to the Masamune. Once one player has completed the process of upgrading the KT-4, all players in the match can upgrade it for free, by going up to the table where the upgrade was completed. However, if multiple players have the weapon in their inventory at one time, the ammo consumption of each shot increases. A glitch exists where the player can get another KT-4 from the Mystery Box if they do not pick up their Masamune, although shortly after picking up the Masamune, the player will lose all of their weapons and points and be left with an MR6.
The KT-4 or Masumune may also be used to fertilize a Seed for increased rewards. A single normal shot for each of three rounds is necessary.
KT-4 vs Masamune Edit
|Fire mode||Semi-automatic |
2-3 round charges
2-3 round charges
|Extras||5 seconds longer chain effect|
- Seeds of Doubt (75/Silver Trophy) - In Zetsubou No Shima, the one must be saved.
- Herbal Remedy (20/Bronze Trophy) - In Zetsubou No Shima, use a plant to return to life.
- Crop Duster (15/Bronze Trophy) - In Zetsubou No Shima, kill 10 zombies with a single shot of the KT-4.
- Web of Defeat (5/Bronze Trophy) - In Zetsubou No Shima, remove webs in every possible way in one game.
- The full name of the weapon, Kusanagi-no-Tsurugi, is also known as the name of a legendary Japanese sword, one of the three Imperial Regalia of Japan. Its upgraded form, the Masamune, is also the name of a legendary Japanese swordsmith.
- On the side of the KT-4, there reads "731細菌戦の研究機関", roughly translating to "Research Institution 731 of Bacterial Warfare". This is a reference to Unit 731, a Japanese covert research group on whom Division 9 is based.
- The KT-4's serial number is 02182016 and Masamune's is 03182016.