The Cursed Dual Katana, often called CDK, are among the most difficult weapons to unlock in Blox Fruits. Inspired by the two swords associated with Kozuki Oden in One Piece, they require extensive preparation: owning Yama and Tushita is not enough, as you must also complete a series of trials in the Third Sea.
The path revolves around collecting six fragments: three for Tushita and three for Yama. Some steps are straightforward, while others rely on timed events, travel across several islands, or random items. Here is how to organize every stage without getting lost.
For another overview of the process, see our guide to unlocking the Cursed Dual Katana in Blox Fruits.
Requirements to Start the CDK Quest
Before you can access the trials, several requirements must be met:
- own Yama and Tushita;
- reach 350 mastery with both swords;
- be at least level 2200.
Once these requirements are met, head to Floating Turtle in the Third Sea. Behind the mansion is a large sealed building. Speak to the NPC in front of its entrance to open the door and access the two scrolls: one dedicated to Tushita and the other to Yama.
Keep in mind that once you accept a trial from a scroll, you must complete it before moving on to anything else. It is therefore best to set aside enough time, especially for challenges involving a raid or a full trip around the Third Sea islands.
The Three Tushita Trials
The Tushita scroll offers three trials. At the end of each one, you receive an Alucard Fragment. All three fragments from this path are needed for the next stage.
First Trial: Speak to the Three Boat Dealers
The first trial requires finding three NPCs located near the water and selecting the dialogue option related to forgiveness.
The first is on Floating Turtle. The second is at Haunted Castle. The third waits on Indra Island, near the Third Sea Coliseum area. These NPCs normally sell boats, but the special dialogue option appears during the trial.
After speaking to all three characters, you receive the first Alucard Fragment. You can check that it is in your inventory under valuable items.
Second Trial: Take Part in the Castle on the Sea Raid
The second trial depends on the Castle on the Sea raid, which occurs every 75 minutes. You must go there during the event and defeat at least one or two raid-related enemies to complete the objective.
This stage cannot be completed freely because of its spawn timer. A private server can make the fight easier, but it does not remove the wait for the raid. Once the event ends and your participation has been validated, you receive the second Alucard Fragment.
Third Trial: Big Mom and the Torches
The third stage requires fighting Big Mom on Cake Island and defeating her in under two minutes. This condition opens access to a separate area, where you must defeat enemies and light three torches.
The groups of opponents can be numerous. A fruit that makes area damage easier, such as Buddha, can speed up the clearing process. After activating the third torch, a boss appears. Once the enemies are defeated, a door turns white: go through this portal to receive the third Tushita fragment.
The Three Yama Trials
The Yama scroll follows the same principle: three trials and three Alucard Fragments. However, this set includes one of the longest stages in the entire CDK quest.
First Trial: Take Between 8,000 and 10,000 Damage
The first task is direct: a player or NPC must deal between 8,000 and 10,000 damage to you. Once the threshold is reached and the completion message appears, you receive the fragment.
It is important to check the message shown before leaving the trial. If no message confirms that you obtained the fragment, you must try again.
Second Trial: Defeat the NPCs Marked in Purple
Yama’s second trial is the most time-consuming. The objective is to travel around the Third Sea and defeat every NPC carrying a purple dot, until you receive the message confirming that you have obtained the Alucard Fragment.
An efficient route is to start at Port Town, then continue to Hydra Island, the Great Tree, Floating Turtle, Castle on the Sea, Haunted Castle, and finally Cake Island. Enemies at Haunted Castle must also be checked.
Mobility is essential to reduce backtracking. The Portal fruit is particularly useful for moving between islands. Without this travel option, the stage can take much longer. For a different look at extended progression in the game, read our Blox Fruits level-up challenge using only found fruits.
Third Trial: Hallow Essence and Soul Reaper
Before accepting Yama’s final trial, it is advisable to obtain a Hallow Essence. This legendary item can be obtained from Death King at Haunted Castle through rolls that use Bones.
This preparation matters because without Hallow Essence, it is impossible to summon Soul Reaper and therefore complete the trial. Bones are notably obtained by defeating skeletons, which may require some farming.
Once you have accepted Yama’s third trial and have a Hallow Essence, summon Soul Reaper at Haunted Castle. The goal is not to defeat him: you must let him kill you. If the teleportation to the special area does not trigger, you have to try again. Each attempt may cost Bones, which is why proper preparation is useful.
In this other area, the principle is similar to Tushita’s final trial: defeat the enemies, light the three torches, then use the newly accessible portal. This gives you the sixth and final Alucard Fragment.
The Final Battle to Obtain the Cursed Dual Katana
Once all six fragments have been obtained, the final room becomes accessible. Place the fragments in the designated mechanism to trigger an animation that opens the way to the final battle.
Before entering, you must have stat points invested in Sword and deal enough damage. The final boss must be defeated to receive the Cursed Dual Katana.
After your victory, enemies may continue to spawn. They are unlimited, but they grant neither stat points nor useful rewards, so there is no need to stay and fight them. The quest is complete as soon as you obtain the CDK.
You then only need to raise their mastery to use the weapon to its full potential. This final effort is far less restrictive than the unlock itself, which mainly requires organization, mobility, and patience with timed objectives.
CDK FAQ in Blox Fruits
What level do you need to get the Cursed Dual Katana?
You must be at least level 2200, in addition to owning Yama and Tushita with 350 mastery on each sword.
How many fragments do you need for the CDK?
You need to collect six Alucard Fragments: three through the Tushita trials and three through the Yama trials.
Why do you need a Hallow Essence?
Hallow Essence is used to summon Soul Reaper for Yama’s final trial. Without it, you cannot access the area needed to collect the final fragment.
Which trial takes the longest?
Yama’s second trial is generally the longest, as it requires searching for and defeating NPCs marked with a purple dot throughout the Third Sea.
