The single most powerful dagger in the entirety of OSRS, the Abyssal Dagger requires the wielder to have an Attack level of 70. On average, the player has a 20% chance to receive the Abyssal Dagger when they are using the unsired on the Font of Consumption. This gives it a nearly 1 in 490 chance of dropping from every Abyssal Sire kill.
The Abyssal Dagger exceeds even the Staff of the Dead in both Accuracy and Strength and adds a +5 Attack bonus and +3 Strength bonus to players over the Staff of the Dead. It is generally a stabbing weapon, while the staff is usually a slash-type attack.
The Abyssal Dagger’s special attack is called Abyssal Puncture and is a two-hit attack with a 25% boost to accuracy and a 15% drop in damage, but only consumes half of the special attack energy. The max damage the dagger can do is 40-40 against other player characters, and 46-46 while boosting the effects with a salve amulet and used against undead-type opponents.
It is worth noting that the Abyssal Dagger’s special attack is significantly lower damage than the Dragon Dagger’s special attack. This is most obvious when comparing the max 40-40 damage of the Abyssal Dagger to the max hit damage of 48-48 for the Dragon Dagger, which also only uses one-quarter of the special attack energy.