You can meet this character while completing the main story.

Nick Valentine is a synth detective from Diamond City. Later in the game parameters of this companion might prove to be not high enough. By default, he uses his shotgun, but he can use other firearms as well. You won't find a friend in him if you will steal, hurt the innocent or be very greedy when negotiating prices. He has a good nature, likes helping and fair judgments, even despite the fact that he approves you using drugs (a good way to quickly improve relations) and giving them to others. Whether you will kill Bobbi or convince her to leave doesn't matter.Д¬ompanion's unique skill: Isodoped - thanks to obtaining maximum relation level with this companion, you will receive a permanent perk that increases the speed of critical bar's loading (while using VATS) by 20% when you have 250 or more rads.Д¬ompanion's advantages and weaknesses: John Hancock is a pretty 'stable' character, you shouldn't have trouble with gaining his sympathy and with improving your relations with him. At its end you must also pick Fahrenheit's, the security chief of Hancock's warehouse, side. However, simply completing the quest will be not enough. He will join you after completing The Big Dig quest for Bobbi. Location where you find the companion: The companion can be met any time you want, in his house in Goodneighbor. The disadvantage of traveling with Cait is the fact that she might not like you making righteous decisions - it could make your relations with her worsen. Additionally, you can use her to open the hardest locks. You can ask why does he want to 'get rid' of the woman, but it will not change anything.Д¬ompanion's unique skill: When traveling with Cait, your action points will regenerate faster whenever your health drops below 1/4 of the basic value.Д¬ompanion's advantages and weaknesses: Cait is very good in combat and additionally, due to the drugs she take, she is more resistant than most other companions. He will ask you if you want to take Cait as your companion. Once all the enemies are dead, enter the large cage and talk to Tommy. You will be forced to participate in some more battles after you get close to a big cage.

Once you reach the destination, you will have to defeat a group of bandits. Location where you find the companion: Cait can be found in the Combat Zone located in the central part of Boston.

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