Guild Wars 2

Periodically, there are Hearts which require you to don a disguise and infiltrate an enemy base to sabotage it.

And pretty much all the time, you take on the appearance of a “human”.

Now, for Syvlari, this wouldn’t be very complicated, as they’re generally the same height and shape.

But how does a 9 foot Norn or a 3 foot Asura disguise themselves as humans?
I would also imagine a Charr would also find it problematic donning this disguise.

The one I just did involved Bandits.
Although they’re rare, I have seen Asura and Norn bandits, so it wouldn’t be improbable that you could pass yourself off as one of those!

Mesmer enchantments.

I went with my friend, who is a sylvari, to one of his quests that required a disguise. I was a norn, and another one of our friends was a Charr. We were disguised as the nightmare court or something. Pretty funny.

I went on one of those (story) quests too – except, when the time came for me to don my disguise (I’m a max height female Norn), I was actually squeezed into a Sylvari plant gown. My physical form wasn’t altered at all. It was hilarious!

I think most of those disguises are magical/mesmer illusion, rather then a physical disguise

Right, it’s not like a “skin suit” that you see the Slitheen use in Doctor Who, for example.

In Metrica Province, there is a heart quest which require getting into small, perfectly matched for asura, golem suit. It was funny to see a giant norn fitting into tiny, half of his size, golem.

Beside that, other disguises are mostly mesmer illusions. There’s even a heart quest where you disguise as a Risen.

I always thought it was a transformation tonic, which were wide spread in gw1 and are found in gw2.

Embolism.8106:

Mesmer enchantments.

That’s the explanation for a lot of disguises.

Not all of them, but most. Beyond that, “game mechanics.” For when you go into a shared storyline, remember that your friends aren’t there in lore. Also remember that models are shared among all generic NPCs – and that’s what you get. These are mechanical “limitations.”