“Raiders are the scourge of the Wasteland, in the Commonwealth and everywhere else. Loosely organized, with a power hierarchy based on pure ruthlessness, they will attack anyone at any time... for any reason.”— Fallout 4 loading screen
The raiders of the Commonwealth are organized into gangs of various sizes and follow a strict hierarchy based on seniority and ability within the gang. They can be found all over the region, but are especially concentrated in Boston, and viciously defend their turf from anything not in their gang, including super mutants, the Brotherhood of Steel, and other raider gangs.
A common raider is the weakest of the cannon fodder found in Fallout 4. Armed with pipe guns and little health, they tend to survive only a few hits, even from early game weapons, before succumbing.
Raider scum are little more than raiders with slightly beefed up stats. They usually are armed with pipe weapons and crudely made welded armor, and also leather armor. The armor they equip may also have a few low level upgrades on them.
Raider scavvers are basic raiders that may have a wider assortment of armor or weapons; they are the most common raiders that will spawn in raider power armor. Raider scavvers are also the lowest level raider that can occasionally be seen with the sturdy variant of raider armor.
Stronger than the raider scum and raider psychos, survivalists tend to have more health and hit harder. They will typically hide behind objects and blindfire around them. When changing hiding positions they will take well aimed shots.
Raider veterans are battle-hardened warriors. They are among the toughest raiders. These veterans are raiders who have managed to survive the perils of the wasteland for the longest amount of time. Armed with higher tier weapons such as combat rifles, assault rifles and on occasion laser weapons. These enemies are further bolstered by a high health pool and segments of combat armor. They are almost never encountered alone, in fact they sometimes act as bosses for mid level areas. Raider veterans around Hyde Park and the Quincy Quarries may be seen with sturdy combat armor, along with heavy raider, leather and even metal armor.
Raider bosses are unique, named raiders who lead a particular group of raiders and can be found at various specific locations. Raider bosses have the same stats as one of the regular raider types, depending on the player character's level, although they typically spawn at a higher tier than their regular raider minions (i.e. if the raiders in the location spawn as raider psychos and raider scum, the location boss may have the stats of a raider waster). Some of them are also equipped with better-than-normal equipment, such as power armor. An example of a raider boss is Boomer, the raider boss in Outpost Zimonja.
While undetected around them, some raiders can be overheard talking to themselves that killing wastelanders is "nothing personal," and also expressing their hopes that "the next one dies clean."
Additionally, after clearing a named raider leader's gang, you may overhear other raider gangs discussing the former being wiped out.
Unlike raiders in the previous Fallout games, these raiders have access to their own power armor.
Raiders now have a more human aesthetic, as they can be heard saying "It's either you, or me" in a shaken, unconfident tone, indicating the need to justify their own actions, showing many to have a fragile conscience underneath the sadistic exterior.
Despite the fact they are regarded as the most technological inferior faction (at least compared to the other major factions) in the Commonwealth, they are surprisingly very formidable, even for high-level player characters. At high levels, raider veterans are very common and are difficult to kill because of their high health, their powerful weaponry, and their extensive use of armors.
When a faction checkpoint is being attacked, raiders are exclusively seen using raider power armor, giving them a higher chance to win, even if they are facing the likes of the Brotherhood of Steel.
Sometimes they can be found talking about tales from the wasteland, one of them being grenade guy.
Ghoulified raiders can be found in various locations such as an entire gang of ghoul raiders at Quincy Quarries, one at the upper level of Monsignor Plaza, and one in the truck trailer on the path to Outpost Zimonja.