How to Unlock and Upgrade Black Flash in Jujutsu Zero Guide

Black Flash is a special damage mechanic in Jujutsu Zero that works differently from normal Cursed Techniques and weapons. It can become extremely powerful when combined with the right stats and build. This guide covers how to unlock Black Flash, complete all of its upgrade quests, and build your character for high damage.

How to Unlock Black Flash

To start unlocking Black Flash, find the Black Flash 1 NPC near the spawn area. You need to meet these requirements:

• Reach Level 400
• Pay 150,000 Yen

After completing the quest, Black Flash will be unlocked.

To activate it:

• PC: Hold M1, then press M2 twice.
• Mobile: Hold the M1 button, then tap the screen twice.

Black Flash damage is affected by your character’s stats and also includes damage based on the enemy’s current HP. This makes it especially useful against bosses with very large health pools.

How to Upgrade Black Flash

After unlocking the first version, you can continue the quest line to unlock stronger versions.

1. Black Flash 2 Quest

Find the Black Flash 2 NPC near the SHR Doctor. The requirement is simple:

• Use Black Flash 1,000 times

The quest counts each activation as one use. It does not matter whether you hit one enemy, multiple enemies, or nothing at all.

A simple way to complete this quest is to stand near a wall and repeatedly activate Black Flash. You do not need to find enemies just to increase the counter.

Once you reach 1,000 uses, return to the Black Flash 2 NPC to claim the upgrade.

2. Black Flash 3 Quest

The final upgrade comes from the Black Flash 3 NPC, located underneath the Recruiter NPC. This quest requires:

• Use Black Flash 10,000 times

You can use the same method as the previous quest. Stand near a wall and repeatedly activate Black Flash until the counter reaches 10,000.

Once you finish the requirement, return to the NPC and complete the quest. You will then have the final Black Flash upgrade.

Best Black Flash Build

Black Flash benefits heavily from offensive stats. When building your character, focus on:

• Attack
• Critical Rate
• Critical Damage

Your Cursed Technique, Clan, Gear, Emblem, and Accessories can all help increase your overall damage.

A strong setup from the guide uses:

• Clan: Amon
• Cursed Technique: Shrine
• Passive: Sukuna’s Mark
• Accessory: Cursed King Tattoo
• Gear: Your strongest available gear
• Emblem: Your strongest available emblem

Make sure to upgrade Amon and Shrine as much as possible. For your other equipment, prioritize items that provide more Attack, Critical Rate, and Critical Damage.

Why Black Flash Is Strong Against Bosses

One of the biggest advantages of Black Flash is its additional damage based on the enemy’s current health. This means Black Flash can hit extremely hard when a boss has a massive amount of HP. However, the bonus damage becomes lower as the boss loses health.

Because of this, your Black Flash damage against a full-health boss can be much higher than the damage you see when attacking a boss that is already close to being defeated. With a strong build, Black Flash can reach hundreds of millions of damage and potentially go into the billions against high-HP enemies.

Black Flash takes some time to fully upgrade because the final quest requires 10,000 activations, but the process itself is straightforward. Once you finish the three quests, focus your build on Attack, Critical Rate, and Critical Damage. The combination of Amon, Shrine, Sukuna’s Mark, and Cursed King Tattoo provides a strong setup for Black Flash, especially when fighting bosses with extremely high HP.