The Pureblood Dagger is one of the many weapons that can be acquired in the Nightmare. It can be purchased at a price of 6,600,000 gold from MANAGER SUPREME in the MYSTERY STORE or as a possible reward from Guttermouth Cells.
In appearance, it is a short-bladed dagger with a jagged, blood-red blade attached to a gray, roughly-made handle. The jagged parts jutting from the blade and handle could resemble either dripping blood or the fangs of a blood-sucking vampire.
The normal slash attack is short-ranged but swift, consuming 1-2 stamina points each time. Each slash lasts about a second or less, allowing for the kind of rapid, frequent attacks one would expect from a dagger.
The special ability of the Pureblood Dagger is titled 'Blood Sap', which, upon activation, causes the player to grip the dagger with both hands and slash downwards from their right shoulder to their left waist, dealing the basic attack's damage to foes and restoring a portion of health equivalent to 50% of the damage dealt, which can be increased by using damage bonuses. Unlike with standard melee attacks, the player is not forced forward when using Blood Sap and can move freely while attacking. The special ability's cooldown lasts for 16 seconds before it can be used again.
The most important quirk the Pureblood Dagger, subtly implied by the weapon's description, is how all three of the damage bonuses change its effectiveness. The special attack is most effective when the player only has a high amount of one type of damage bonus, while the other two are as low as possible. Having a large amount of each damage bonus severely limits the weapon's ability to perform well in combat. In comparison, having only one type of damage bonus will result in having a 200% damage bonus applied to the dagger.
- The Nightmare Prowler Hat can be seen with a Pureblood Dagger thrust into the front brim, though it cannot be removed or otherwise interacted with.
- During development, it was originally called the Crimson Dagger.
- During the Balance Update [v1.31], the Pureblood Dagger's base damage was increased from 140 to 175 points.
- It was also updated to scale off the purity of the highest damage bonus the player has instead of specifically Melee bonuses.
- The Pureblood Dagger's damage bonus is added using the following equation: HV + (HV - LV1 - LV2), where HV is the player's highest damage bonus, and LV1 and LV2 are the other two bonuses.