Guild Wars 2

Hello everyone basically a party of 5 including me were defending a supply camp (commander wanted to do it :P) we had 2 acs high up in a tower. So all ready, then a guardian and engi comes (only 2) builds a ballista in literally 3 seconds one shots both acs that were high up in the tower then believe it or not more or less the lone guardian one shots us all. I have mesmer with high toughness and 2100 health and staff defence trait. Also the other party members were 2 guardian, ranger and an ele. The commander then later told me that those 2 had been building acs and ballista without the need to resupply. Only 2 people.

I really should have taken a screenshots but I was completely taken back and forgot until party started to discuss the 2 people. Btw I am not a bad mesmer :P I normally never have too much problem with guardians. Infinte supplies and one hit acs and one hit attacks is it a hack???

TY