|Side Quest: Stop Gizmo|
|Complete Get Gizmo's confession quest.|
|Tell Killian about Gizmo's plans.|
|Speak to Lars.|
|Kill Gizmo and Izo.|
|Reward: 600 XP|
To complete this quest, the Vault Dweller first needs to get Gizmo's confession. Once 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 spoken to and the process agreed, they 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 is given no choice but to battle them and kill Gizmo. Once they have been killed, the unique 9mm Mauser can be found on his corpse.
If the Vault Dweller refuses to go when asking Lars, the quest will be failed. Going in this way, one only has to fight Gizmo and Izo. The other guards won't go into the small room to fight and will disappear after this scene.
- 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.[verified]
- 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.[verified]