Wasteland 3

This achievement is done on the western side of the Security Level in the corridor leading to Maximum Security. You will need to micromanage two to three rangers. First, select a ranger you don't mind being inflicted with 10 stacks of Holy Radiation or put a Hazmat Suit on them. Have them go into the irradiated northern hall and stand on the pressure plate. Next, have one of your rangers go into the southern hall below Maximum Security and interact with the computer. If you have Nerd Stuff maxed then you can immediately disable all of the lasers. If not, then you will need to guide another ranger through the lasers as you switch between three different laser configurations.

Once you are all the way through to the Maximum Security door, make sure to get your ranger out of the hall with the computer if you didn't do the Nerd Stuff check as a laser wall will block them in once you flip the switch beside the Maximum Security door. Now flip the switch and open the door to find the Night Terror. Select the top dialogue options to get it to join you.

Once it is following you, speak to it again. Say "Do you want some candy?" and then select "Give the Night Terror some random remains." This will feed random items from your junk to the Night Terror. You need to feed it 20 times before it falls asleep and the achievement pops.