Cazador

Cazadores are mutated insects found in the Mojave Wasteland, The Big Empty and Zion Canyon in 2281.

Biology
Cazadores are tarantula hawk wasps, who have been mutated by Dr. Borous in the laboratories of the Big MT. The resulting creatures have distinctive amber orange wings, a blue-black carapace and blood-red eyes. They have a fast and rather erratic flight movement and a venomous attack which can lead to a quick death if not soon treated with antivenom, though high level or high HP players may outlast the damaging effects of the venom. The spikes on their back inflate and deflate when idle and attacking.

Cazadores are more common in mountainous regions of the Mojave. They chew wood fiber and mold it into a paper pulp with which they create large basket-shaped nests, many of which can be seen at places such as Bonnie Springs, the road heading towards Jacobstown, and the boathouse at Callville Bay. The cazadores' original breeding ground in Big MT is the Z-14 Pepsinae DNA splicing lab.

Gameplay attributes
While a sting from a young cazador isn't highly damaging, the sting of an adult deals notably more damage. They are very fast and hard to escape from without crippling their wings. They attack in large swarms, and possess a very strong poison. Higher levels of Endurance can give a slight chance of resisting the poison. The only ways to deal with the venom is with antivenom, using a prophylactic such as blood shield (introduced in Honest Hearts) which temporarily boosts poison resistance, having the Heartless perk (which negates all chances of being poisoned) or the Cardiac Arrest perk (which reduces the chance of being poisoned by 50%). These last two options are only available to users with the Old World Blues add-on.

Curiously, cazadores cannot swim but will always try to follow the player into the water, at which point they will quickly drown. Crippling a wing via V.A.T.S. slows them down immensely, and crippling both wings causes them to have to fly at an extremely slow rate.

Cazadores also seem to be territorial, in the sense that if you step too close, they will engage. It is therefore best to just steer clear of them altogether, unless you're well-equipped for the encounter, meaning that you have some anti-venom and other supplies such as Stimpaks and Psycho.

Cazador
Cazadores are large with distinctive orange wings, a blue-black carapace, blood-red eyes, a spiky upper abdomen, and a high and rather erratic flight speed. Cazadores are common in mountainous regions in the Mojave Desert, and go around in groups of 2-5.

Young cazador
Young cazadores are often found near other cazadores in mountainous regions (presumably members of the same colony, hive, or swarm). Young cazadores are identical in appearance to regular cazadores but are about 3/4 to 1/2 the size. Though their poison is weaker than that of the adults, they have an above average Agility, making them rather hard to hit.

They also prove to be quite a hassle because of their swarming tactic, which involves the entire group swarming their target in an attempt to overwhelm it via numerical strength.

Legendary cazador
The only one of its kind, the legendary cazador has twice as many hit points and significantly more attack power than a normal adult cazador. The legendary cazador is one of the four legendary creatures found in the Mojave Wasteland. It is encountered at the end of the cazador-infested Silver Peak Mine. Sometimes it will show up after the player clears out all the other cazadores or after reaching the second floor of the cave.

Giant cazador (Honest Hearts)
Giant cazadores are encountered all over Zion Canyon as part of the Honest Hearts add-on. They are one of the most vicious creatures in the add-on, and can be found in various locations outside of Eastern Virgin and the Sorrows Camp. They are usually in groups of around three, but it is not uncommon to see groups of other sizes. And as their name implies, they are much larger than a normal cazador.

Specimen 73 (Old World Blues)
A unique cazador found in The Z-14 Pepsinae DNA splicing lab in the Big Empty. Judging by the name it was probably some sort of experiment. It is a stronger and more powerful version of a regular cazador and even has more health than the legendary cazador. The main advantage of this unique cazador, though, is its incredible speed.

Appearances
Cazadores appear in Fallout: New Vegas, are mentioned in the graphic novel All Roads, and also appear in the Fallout: New Vegas add-ons Honest Hearts and Old World Blues.

Bugs

 * It is impossible to target the head of a cazador in V.A.T.S. unless it is striking forward with its stinger, the player is right on top of the enemy or it is moving on a slope towards the player. Without meeting these conditions the head can never be cycled to as an option in V.A.T.S (only the antennae). This also applies to PCs when using an Xbox 360 controller, but not when selecting targets with the mouse.
 * It seems to be possible for them to fall through the map and fly about under it. This will drive your companions crazy, since they will be targeting them but unable to hit them. The cazador cannot sting the non-player characters or you either, but they will continue to fly back and forth attempting to attack. If you are on a rise, you will get the name and a health bar when you point a gun at them, but they are invisible and it is clear from the angle of your gun that they are under the map. Attacking with the Ranger Takedown maneuver may fix this bug.
 * Poison does not appear to wear off companions in the 1.2.0.31x patch after combat. Dismissing the companion and re-hiring them at their home location or the Lucky 38 seems to bypass this. It will wear off after 30 seconds, administering stimpaks to companions will cause the whole damage-over-time to be applied at once which could bring them to negative hp.
 * On the PC version, can be fixed by, in the console, selecting a companion and typing.
 * Sometimes (or all the time, if your system is affected), if cazadores are in the area, even if you can't see them, you will hear the poison hissing sound loud and close as if you had been poisoned by them. Essentially, you will hear the sound when a cazador anywhere in your active cell poisons something - the attack might not be on the player character or a companion, since even a distant cazador battle will trigger the sound.
 * If you use the flamer against them, they sometimes freeze in the air while on fire giving you a chance to kill them or run away.
 * Sometimes a cazador may spawn underground and still be able to attack you, but you cannot attack it. This was confirmed at the Callville Bay cazador's nest. The only way to kill it is to have a companion to do the job.
 * Sometimes when selecting cazadores on V.A.T.S., it tends to freeze your character from shooting (your character will move around but won't shoot), leaving the cazadores free to attack you for a good 10–15 seconds. Simply restarting the system should do the trick.
 * Rare occurrences of cazadors being able to poison you when they are in no way close enough to do so, seems to only happen in V.A.T.S..
 * Sometimes, the legendary cazador just wanders around the cave without attacking the player, making it an easy target for the player.
 * In Silver Peak Mine, cazadores may not show up as red blips on your heads-up display even though they can be targeted using V.A.T.S.
 * In the add-on, Honest Hearts, cazadores will often cause severe lag, especially when confronted in groups. The FPS rate can be bogged down to less than 10FPS in some instances. Killing them during the lag does fix the problem, and longer play sessions seem to intensify the bug.