This is one of the most powerful weapons in Fallout 3 and Fallout New Vegas. Alien Laser Gun is again present in Fallout 4. Although it is far from the ultimate weapon of the game, you can increase your ability "Pistolero".
To find this gun, go to the middle of the Commonwealth, in the area just in the red circle on the Pip-Boy as shown below.
At this point of the map, you will arrive at the scene of a crash ... And not just any, since the crash in question is a flying saucer! This is the first step to get to the alien gun. Start by examining the crash site and spot the green traces on the ground. Follow the tracks to get to a cave. It is inside this cave you will find an alien not quite recovered from his accident. It will not be hard to kill. It will do more than to search him to get the gun, do not forget to search his bag located just off the corner where the alien was hiding because ammunition there.
Make good use of your weapons as the alien munitions are not found in the Commonwealth! Once you are out of stock you will get more! Fortunately, it is possible to change the weapon using a weapon set to change the type of ammunition. And you lose 10 points of damage, but the ammunition will be much easier to find.
Here's how to find the gun. Also note that if you are just starting the game it will not be possible to find the weapon. Indeed, it must be level 20 in order to unlock. You will hear a resident of the Commonwealth that he saw an object fell from the sky ... It is from this point that the crash will be available.
Also note that it is not required to hear an NPC say that an object fell from the sky. From level 20, the crash should be accessible.
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