Guild Wars 2

What are guardians best at in wvw?

Thanks for the awesome replies to my admittedly dumb question. The community for this game has rocked so far.

My guardian seems to have high surviveability.
Is there a build for warriors that makes them feel indestructible at the cost of lower damage?

I applogize for not being more clear on the role I want to have in WvWvW. I have a level 30 engineer and a level 20 guardian.
I had a hard time finding a decent build and toolbar setup for engineer to feel effective at sieging and defending. I think it would be worth looking back into that class since I did drop it because I didn’t fully understand it.
I made guardian hoping to feel more useful, but it’s lack of range is disappointing. I feel like I serve no purpose in anything other than battles out in the world.
I’m tempted to turn to warrior for their ranged and melds weapons.

Which class has the best versatility for WvW?
Im looking for a class that is useful in all WvW situations.
Attacking, defending, etc.

Thank you.