Crawmerax the Invincible

Crawmerax the Invincible is a boss in The Secret Armory of General Knoxx.

Involvement
He appears in the mission You. Will. Die. after you finish the main story included with the DLC.

Information
One of the most difficult bosses, if not the most time consuming in Borderlands, Crawmerax is at level 64 while players are capped at a mere 61.

Even a four player party will have a decent challenge of defeating him, although if everyone in the party is equiped properly, and of high level, things go more smoothly. It is not recommened to be of a low level and/or play solo when attempting to take on Crawmerax as you will more than likely lose.

Crawmerax the Invincible is a fully grown Crab Worm with a heavily armored, spiked shell. The Larva Crab Worms seen in the Lost Cave and the Trash Coast are puny by comparison. He looks like a titanic grayish-brown version of a Larva Crab Worm with glowing purple critical-hit spots on his body.
 * He is surrounded by level 61 Green Craw Worms, Craw Maggots and level 62 Armored Craw Worms.
 * To reach Crawmerax once inside his lair, you must go up a very long lift to the top of a plateau. (Lift taking 30 seconds to go down and 30 seconds to go up.)
 * He has a chance of dropping the super-rare Pearlescent weapons.
 * Crawmerax is level 64 in both playthroughs, although he and his minions have much less HP in the first playthrough. This is probably for players to get the same damage reduction encountered when facing overlevelled enemies.

Strategies
A less scattershot guide.

Attacks and Behaviors
Crawmerax is a daunting opponent, but the basis of his attacks narrows down to four main behaviors:
 * 1) Bite/Claw Attack: Crawmerax approaches the player, then proceeds to lunge and bite the player, no different than the attacks that normal Craw Worm enemies unleash. The range of this attack is phenomenal, but he does require medium range in order to perform this.
 * 2) Glob Storm: Crawmerax rears backward, then exhumes about ten purple globs against the opponents. These globs are each launched smart, meaning that Crawmerax will aim the globs at a position predicted that the player will be based on his or her movements.
 * 3) *For the least number of globs to hit, standing still will force the globs to be aimed in one spot. Due to the velocity and splash radius of these globs, only the first few should be attempted to be dodged in this manner. Changing movement direction drastically during dodging also increases the chance of avoiding the globs.
 * 4) *During this attack, Crawmerax nearly freezes in position, leaving his vulnerable spots stationary. Teammates positioned behind Crawmerax should take this opportunity to deal some damage. Players in front of Crawmerax will want to take aim at his eyes, since this is the smallest and sometimes hardest to hit of his weak points. A few well placed Sniper or Masher rounds can disable the eye, but leaves the player vulnerable to the globs.
 * 5) Cry for Help: Crawmerax exerts a roar and burrows underground, reappearing after some time in a different location on the battlefield. This attack is most often seen when the number of minions on the field dwindles, or when Crawmerax has lost some portion of his health. At this point, Green Craw Worms, Craw Maggots, and Armored Craw Worms will spawn on various locations in the arena.
 * 6) Monstrous Dive: This is easily Crawmerax's most devastating attack to a group of Vault Hunters, as the radius of the attack covers a great portion of the battlefield. Crawmerax will burrow underground, then leap into the sky creating a huge shockwave that sends players skyward. This attack completely wipes out shields and does severe damage to all that are hit.
 * 7) *Players can avoid damage from this attack entirely by using the pillars or other battlefield obstructions as cover.
 * 8) *Normally, players are sent flying into the air when this hits them. To avoid the launching effect of the shockwave, jump before Crawmerax dives up into the air. This will nullify the launching effect of the attack, but the damage is still taken.
 * 9) If you are on one of the lower cliffs near the edge he can lunge at you and land on the ledge with you. It doesn't happen often, but if it does you need to get out fast or he can trap you there so you can't move. Needless to say he will down you and start chewing on your head.
 * Be sure to distinguish the difference between Cry for Help and Monstrous Dive, as they both have similar animations. While both involve Crawmerax burrowing underground, he roars during Cry for Help, but not Monstrous Dive. This can help players brace for impact should a Monstrous Dive be happening nearby. You will also notice that when Crawmerax prepares for the Monstrous Dive, he buries himself backwards, unlike while he performs the Cry for Help, where he buries head first.

Weaknesses

 * Green Craw Worms are weak to Fire damage and their eye is their main weak point.
 * Craw Maggots are weak to Melee damage and Shock damage. Their eye and underbelly are their main weak points. A high-level Thunder Storm can kill them in one or two shots up close. Also notice that they are stunned when shocked.
 * Armored Craw Worms are weak to Corrosive damage has the same critical location as any other Craw Worm, its eye. The Pestilent Defiler disposes of these quickly
 * Crawmerax is weak to Shock damage and his weak points are all highlighted by purple glowing spots- More specifically, his back, his eye and the backs of each pincer. Although the orbs that are the weak point of each pincer are on the back, they may also be hit from the front by aiming at the joint where the two halves of each pincer meet. Many shots fired at this point will miss, but some will get through, so high fire rate weapons are best for this purpose.
 * By shooting Crawmerax in the eye and eliminating it, Crawmerax's ability to discern where the Vault Hunters are is significantly hampered. This does not mean that Crawmerax cannot locate the players, as he will pursue targets. Crawmerax's area of awareness is cut down, allowing for players to escape more easily from being chased (and inevitably eaten). Crawmerax seems to be able to locate players that are firing weapons, moreso when the weapon is fired at him directly, better than those that are not. Because of this, multiple players firing at a blinded Crawmerax will often cause him to have difficulty focusing on one player.

Glitches

 * There is a glitch where Crawmerax himself will fall off the cliff and become trapped. While it's possible to kill him from this position, the drops will be completely unreachable.
 * Just before you go through the red barrier while going up with the elevator, it will seem like you are being squished. If you jump at the right moment, you'll be superlaunched into the lair. Usually, spamming the jump button works.
 * When going up the elevator, jumping on teammates will push them through the elevator floor and leave them stranded at the bottom of the shaft - the call button is too far out to engage. Another teammate has to respawn and call the lift to free him.
 * It is also possible for the aforementioned glitch to be performed due to connection to the host. If all 4 team mates are travelling upwards in the lift and one person has a poor connection quality, they will just fall through the lift and be stuck until somebody dies (or teleports back down using the button) to call the lift down
 * There is a possibility for Crawmerax to use his area attack and knock players on to the surrounding cliffs, making him very easy to kill if you're a siren as he can only use his ranged attack on you, which is avoidable by using phasewalk.
 * Killing Crawmerax multiple times without picking up any drops may cause new drops to be unavailable to players who aren't the host. Bandwidth constraints seem to play a role here. These drops do appear over time and/or from death/re-entry via elevator.
 * If any of the craw maggots or other worms knock you off the back of the cliff, you might survive the fall, although your screen stays red around the edges and you have to kill yourself with a grenade or rocket in order to reset.

Video
Video:Crawmerax The (Not So) Invincible|One of the Strategies implemented against Crawmerax to near guarantee success. Video:Borderlands - Easy Way to Kill Crawmerax Solo|See 0:00-4:50

Video:Borderlands Crawmerax the Invincible Solo Fight (Siren)

Video:Siren's Dance with Crawmerax|Breakdown of taking down Crawmerax as a Siren.