"Oh aren't you adorable?"

The Major Bio-mechanoid (Walker in the Serious Editor) is a large, red bipedal cyborg that has made its appearance in many Serious Sam games. A dangerous opponent, they are armed with two rocket launchers that are attached to their sides, which makes them some of the deadliest enemies in Mental's Horde.


Major Bio-mechanoids are biological organisms that have been designed by Mental from the ground-up with avian DNA, allowing him to customize them to his needs. They run on a battery that can be recharged by hooking it up to an external power source.

Majors are one of the deadliest enemies in the games; they have high health points and their rockets can inflict a lot of damage, especially if they explode in close proximity to the player.

In Serious Sam 3: BFE, unlike their classic counterparts, Major Bio-mechanoids can strafe left or right and shoot simultaneously.

In Serious Sam: Double D, Major Bio-mechanoids can be jumped and walked on without being hurt when the player touches it. In addition, jump pads will stick on dead ones, giving one more height to reach a platform.

NETRISCA informationEdit

"A biological mechanism grown in Mental's bio-tanks. Its genome is programmed to give it biologically grown mechanical parts. Separately manufactured rocket launchers are attached to biologically designed side slots and are directly connected to its nervous system. The large head serves mainly as a battery containment. The Bio-mechanoid's intelligence is limited mainly to seek-and-destroy. Servo motors controlling its movement are very loud. This will give you a hint to the Bio-mechanoid's presence."


Major Bio-mech SS3 boss

The Major Bio-mechanoid as it appears in Serious Sam 3: BFE.

In Serious Sam 1, Major Bio-mechanoids first appear in the Valley of the Jaguar, where they are accompanied by Minor Bio-mechanoids. Later on, they become more common, serving as support to lighweight troops.

In Serious Sam 3: BFE, the first Major Bio-mechanoid is encountered in Broken Wings where it shoots down a helicopter that was meant to extract Sam out of Cairo. It serves as a boss, complete with a health bar. Subsequent Major Bio-mechanoids serve as heavyweight front-line troops and can be encountered from time to time. Usually there are only one to a few major Bio-mechanoids in combat at a time, supporting weaker front-line enemies. They are more common in co-op.

Attacks and statsEdit

A Major Bio-mechanoid does not fire its rockets simultaneously, which can help it target a particularly mobile target. For example, if the player is strafing right and a rocket misses, then starts strafing left, the second missile will fire at the player even though they are going in the opposite direction. After firing two missiles, the Major will have a brief cool-down period, often get closer to the player, then start firing again.

Serious Sam 3: BFEEdit

They are not very different from their classic counterparts, with the exception of a few discrepancies: the first being that unlike its classic version, the Major Bio-mechanoid has a "berserk" mode, much like the Scrapjack. This will activate when it runs low on health due to consistent damage, which consists of a rapid volley of missiles. Along with AI behavior which causes it to not always walk in a straight path towards you like its classic counterpart, which can make hitting it with a rocket launcher tricky at certain distances. They also do not shoot a rocket upon dying.

The boss has the unique ability to quickly sprint towards Sam, and can still use its berserk mode when under heavy fire, which is extremely deadly if it happens to be sprinting around the same time. It also has roughly three times as much health as its normal counterpart.


Serious Sam 1Edit

  • A charged up SBC Cannon shot can kill a Major Bio-mechanoid in one hit. This is very useful if the player needs to pick off Majors quickly. Because charged up cannonballs can quickly travel across an area, this makes the cannon useful against Majors at any range. However, this depletes cannon ammunition rather quickly, and it is best to use the cannon against other enemies as well, such as medium Lava Golems, Fiendian Reptiloid Demons and large masses of Kleers and Beheaded Kamikazes.
  • When not having a cannon, rockets and grenades are good options to take them out. The XL2 Lasergun and XM-214-A Minigun work well too, but it quickly depletes ammunition.
  • A Major Bio-mechanoid is a very deadly enemy if left unchecked. Its rockets can inflict major damage, even with splash damage. It should be one of the first enemies targeted in a group of enemies, even if there are fast enemies like Kleer skeletons following the player.
  • A Major's rockets can be shot down with any weapon. Therefore, in situations when a Bio-mechanoid spawns very close, it is recommended to switch to rapid-fire weapon and aim at its weapons.
  • Majors have a different way of firing rockets in Serious Sam HD. Normally, they fired firstly from the left and then from the right. In HD, they fire first from the right, then from the left. This is useful to know when attempting to fire down its rockets. In Fusion, they alternate between firing right and left rocket first.
  • Jumping when Major Bio-mechanoids fire makes them fire rockets further away, thus reducing the chance of getting hit by splash damage of rockets hitting the ground.
  • Avoid standing near or in front of walls. Remember that a Major Bio-mechanoid's rockets will explode on impact and the splash damage can hit you from behind or the side.
  • Major Bio-mechanoids should be considered a medium-priority target when paired with other enemies. Its attacks may be powerful but they are relatively easy to dodge, at least in open areas. In smaller, less spacious places, Majors are high-priority enemies, and should be taken out first.

Serious Sam 3: BFEEdit


  • The Major Bio-mechanoid is very fast, so the player should start sprinting away from it when its getting too close. its rocket barrages are very difficult to effectively dodge if it is near you.
  • It has one major weakness; it can be harmed from the explosion damage from its own rockets. To take advantage of this, the player should position themselves near the center structure in the arena so that the Major's rockets on one side will hit the the wall, doing a good amount of damage to it. Repeating this, along with a few shots from the 12 Gauge Pump-Action Shotgun, will quickly kill it.
  • The hidden Double Barrel Coach Gun and XL2 Lasergun from Into the Spider's Nest are effective against the Major if the player managed to get either of them earlier. The coach gun does double the amount of damage that the pump-action shotgun does if all pellets connect, and the Major's large size makes it easy for most of the pellets to hit, while the lasergun does comparable damage to the minigun and makes quick work of the Major.

As normal enemiesEdit

  • When facing a Major, the player should make sure there's a decent amount of distance between the Major and the player. The Major's rocket bursts are difficult to escape unscathed when the player is close to it. It will attempt to get close to the player in order to give the player less room to avoid its rockets, so if the player sees it walking, they should sprint away from it, then start firing again.
  • The Major Bio-mechanoid can still be easily dispatched from a single charged shot of the SBC Cannon. It has a short charge time, allowing the player to quickly kill it in one shot.
  • A single C-4 Demolition Charge is all that is required to kill one, provided it is stuck onto the Major Bio-mechanoid. Even if the player is unable to toss a charge on it, a small pile of C4 can kill the Major.
  • It is also possible to kill one using the Sirian Mutilator, but this may prove difficult, as the Major Bio-mechanoid will physically pull the Mutilator beam, bringing the player much closer to a potential danger zone. The Mutilator also requires charging near to the point of overheating to kill one Major Bio-mechanoid, this leaves the player very prone to being attacked.
  • The XPML21 Rocket Launcher is effective against the Major, but the player needs to be somewhat close to the Major in order to effectively use it, as the Major can avoid rockets. If possible, use the AS-24 Devastator instead, as its projectiles are fast enough that the Major cannot dodge them.
  • Multiple Majors can be dispatched with either the SBC Cannon, XM-214-A Minigun or Devastator. The cannon's charge-up period is fast enough that it can quickly fire the amount of cannonballs needed to clear out a group of majors, the minigun has a fast enough rate of fire to quickly defeat Majors, and the Devastator's projectiles are fast enough that it can wipe out a group of Majors with ease.
  • When faced with other enemies, the Major Bio-mechanoid is very dangerous because of the large amount of rockets it can fire in one burst. These rockets can do a good to significant amount of damage even if one or two hit, so the Major(s) should be killed before they can hit the player with a rocket or two while the player is pre-occupied with other enemies.
  • On higher difficulties, they should be a medium-priority target, especially when they are not closing in. While the rockets do a lot of damage, they are relatively slow, easy to dodge and can be shot down with rapid-fire weapons. A lot of more lightweight enemies have harder to dodge attacks.

Serious Sam: Next EncounterEdit

  • Strafing left or right is enough to dodge the Major's rockets.
  • When fighting a Major, make sure not to have a wall close to your back. Rockets that strike the wall near the player's back can still do damage via the rocket's explosion.
  • The RAPTOR Sniper Rifle is extremely effective against the Major; one zoomed in shot will kill it.
  • If a RAPTOR is unavailable for whatever reason, a volley of four or so rockets from the XPML4000 Rocket Launcher will kill it. Remember that these rockets will take a while to get to the Major, especially if its far away.
  • The Sirian Power Gun is quite effective against Majors, especially if there are more than one attacking the player. Its high damage output is very useful for killing multiple Majors quickly if the player can't or won't use the RAPTOR Sniper Rifle for whatever reason.
  • Major Bio-mechanoids should be considered a high-priority target. Their rockets can be dangerous if they're left unchecked while dodging other enemies.

Serious Sam: Double D Edit

  • The Major Bio-mechanoid's rockets can be dodged by jumping over them. As soon as the Major's rockets can be seen, jump. This gives the player enough time for it to fly past the player while they're in the air. This works even if the player doesn't see the rocket as soon as it appears.
  • The Major's rockets can be destroyed by shooting them with the player's guns. This can be handy if the player is caught in a situation where they can't run towards the Major, or they are facing multiple Majors and need to neutralize the rockets of one of them while dodging the other's rockets.
  • Gunstacks featuring multiple powerful weapons, such as the LM32 Rocket Launcher and MadDog Grenade Launcher, are needed against the Major Bio-mechanoid. These are the only weapons that can deplete the Major Bio-mechanoid's health in a reasonable amount of time.
  • The 0-4377 Flamethrower works great for destroying it's rockets. Put one on a gunstack and hold down the fire key. While the other guns are firing, the Flamethrower will destroy any incoming rockets if the player hasn't jumped over it.
  • When paired with other enemies, the Major Bio-mechanoid is a real threat. Its projectiles are quite powerful, which can be very dangerous if they manage to hit the player while they are dodging other projectiles. Taking it out ASAP assures that the player will not be hit by its rockets when they least expect it.

Related achievementsEdit

Maintenance time Maintenance time
Blow a Major Bio-mechanoid into pieces.

Behind the scenesEdit

  • An early model for the Major Bio-mechanoid can be seen in Test 1. It's lower-poly, has a completely different skin, and a rougher death animation. Also all earlier builds of Serious Sam had the same model as the one from Test 1.
  • Pre-test 1 images and Serious Sam Origins show that the alpha Major was blue.



Serious Sam 1 & Serious Sam HDEdit

Serious Sam 3: BFEEdit

Serious Sam: Next EncounterEdit

Serious Sam: Double DEdit

Serious Sam: The Random EncounterEdit

List of appearancesEdit