The Dismemberer

 is a unique axe which is added to Fallout 3 with the Point Lookout add-on. It can be repaired with axes.

When someone is killed with it, they have a chance of all of their limbs flying off, thus the name. It also has higher damage, lower AP cost and does 700 points of damage when you critically hit an enemy.

Obtaining
This axe can be obtained by completing Plik's Safari.

Appearances
appears in the Fallout 3 add-on Point Lookout.