Stop Gizmo

Stop Gizmo is a side quest in Fallout.

Detailed walkthrough
To start this quest, the Vault Dweller first needs to complete Get Gizmo's confession. Once the confession is delivered, Killian Darkwater will offer them the option to join him in taking out Gizmo. Should the Vault Dweller accept, they will be directed to Lars. Once Lars has been spoken to, the Vault Dweller will be immediately transported to Gizmo's office, together with Killian and Lars.

Gizmo and his bodyguard Izo will immediately attack, so the Vault Dweller has no choice but to battle them and kill Gizmo. Once they have been killed, the unique 9mm Mauser can be found on Gizmo's corpse.

Rewards

 * 600 XP
 * 500 bottle caps
 * +3 Reputation

Bugs

 * Sometimes after talking to Killian when Kenji shows up, he will not attack Killian. This prevents the quest from starting and so the rewards cannot be obtained. There is no known way around it.
 * Once asked by Killian to record Gizmo's confession, the player character can immediately talk to Lars and fight Gizmo without getting a confession. Killian will also be there and Lars will reward the player character the same amount.