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human
[Warhammer 40k] Why is Terminator armour so completely useless against Genestealers?

In Space Hulk, the massively armoured marines fall ludicrously easily to Genestealer attacks. 

As soon as they enter melee combat they are pretty much doomed, they might as well be naked. This always bugged the shit of me considering how much the lore says how powerful Terminator armour is supposed to be. 

I mean if they can shrug off an anti-tank round or a blast from a heavy lascannon how can a single strike from a Genestealer's claw kill them instantly? Surely a creature the size and mass of a Genestealer couldn't possibly release as much energy from a claw strike than an impact from the aforementioned weapons?
gpt
You have to consider the scaling effects inherent in any game.  You see, one genestealer game piece does not equal one genestealer in "real life."  It more likely represents a whole swarm of genestealers.  However, 1 terminator game piece probably does represent a single terminator.

So in the board game when a genestealer kills a terminator, it represents a situation where hundreds of genestealers swarm out of the bulkheads to mob the lone terminator.  In conjunction with the super charged claws and muscles of the genestealers, it's easy to see how they could kill a terminator.