Why would there even be a 'crusher'?

[Sully]

The way I've always understood it is that the xenomorph takes on part of its hosts DNA etc.  So really, even aside from the place being nuked, why would there be a 'crusher'?  I mean it would only make sense if there was a rhino on the planet.

[Xenomrph]

It's to allow variety in gameplay.

As for the in-universe "why", the game might explain it itself. I'm willing to wait and see if it does.

[[USCM]Winter]

Is because of raditions and that led to mutations

[Xenorgue]

I had emitted the theory that the crusher is a runner changed there praetorian.

[CyberDemon13]

Just a little hive hierarchy list I came up with over on the Gearbox forums. It includes the Crusher.

Just thought I'd reiterate: I don't buy the radiation theory; I'm with Chris, I believe the xenos are immune (or at least resistant) to radiation. On the topic of Praetorians, I do feel they have a unique and important role in the Hive heirarchy. Here's my theory:

1. All eggs are created equal. Every egg comes standard with one "regular" facehugger that, unless certain situations arise, will grow up to be a Warrior.

-Warriors are more aggressive by nature, with their main purpose being host capture and defending the Hive. They use swarm tactics and try to overwhelm the opposition with their superior numbers.

2. Every adult xeno, regardless of host species or caste placement, has the genetic capability to moult into a Queen. Now this only happens in two situations:

A. In the absence of a Queen (death or capture of current Queen); or the depletion of Hive population.

B. In the instance of a xeno being born in isolation (FAR away from the Hive; where the "Hive Mind" is no longer felt).

-So lets say the current Queen were to die, the Praetorians would be first in line to take her place. Any "leftovers" would be the Royal Guard of the new Queen. I like the idea (alluded to in AvP 2010) that before a xeno can moult into a Queen, it must first moult into a Praetorian. So it's sort of like a half Queen.

3. So where do Scouts and Crushers fit in? I'd like to think they are highly specialized variations of the basic Warrior.
         
-Scout- I believe the Scouts specialize in survival. By this I mean they are more cautious than their Warrior counterparts, and prefer to use stealth and fear tactics rather than trying to overwhelm the opposition. They are born when the Hive population is low and the usual swarm tactics would be extremely risky; or when a xeno is born in isolation (such as in Alien). If the latter is the case, they will try to capture/subdue all threats in the area so they can moult into a Queen and begin the egg laying process.
         
-Crusher- I think the Crusher is a specialized variant that shows up in response to some outside force that requires a few larger and stronger xenos to match and overcome it. In this case, the atmospheric processor exploding caused some of the xenos to moult into Crushers so as to beter deal with the situation. Another example could be human tanks, the standard Warrior xenos cannot take down this threat, so they adapt.

The Perfect Organism, indeed.

*Maybe I should've substituted moult with metamorphosize; I don't know, I think moulting is just the shedding of old skin cells, not a transformation into another branch of life (think butterfly, they do moult out of their cocoon, but the process within the cocoon is a metamorphosis). I don't know, I'll leave it for now until I decide lol.

I still haven't decided, by the way, and I may have spelled "moult" wrong. Haha

[chupacabras acheronsis]

Is because of raditions and that led to mutations

radiation doesn't work that way you know.

if the alien genetics could be affected by Alpha and Gamma emisions then they couldn't even reproduce with their hosts.

i am more partial to the theory that it's a recesive trait of the alien, a leftover stage in the cycle that got 'activated', but i can't make much sense of that either. honestly, calling it "crusher" is cheesy and doesn't give it much versatility for biological roles. i prefer the good old praetorian.

[WinterActual]

  I mean it would only make sense if there was a rhino on the planet.

There wasn't rhino on the planet but there was a hampster so....

[PVTDukeMorrison]

I can almost guarantee the Crusher came from Hudson

[Xenomrph]

I can almost guarantee the Crusher came from Hudson

...go on.

[KingAngel ofthe Outergulf]

Bio-Imperative.

[chupacabras acheronsis]

that's not what gearbox said.

[KingAngel ofthe Outergulf]

that's not what gearbox said.

And what did gearbox say?

[chupacabras acheronsis]

radiation mutated the alien. nothing natural for them.

[KingAngel ofthe Outergulf]

The only radiation I have seen effect them is Photon and Neutron.

[Xenomrph]

There's a first time for everything I guess.