Guild Wars 2

When attacked by enemy players I checked my combat log only to discover that some players are hitting for 8,000 a hit against my maximum 800. I’m level 42 with rare yellow weapons and armour.
I checked all weapons stats and the weapon that makes the most damage in GW2 is 1,200 and even with many stacks that doesn’t add up to 8,000.
What are they doing to get such hits? Crits don’t add up to that either, it makes no sense..?

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Worked fine until 11:52 GMT