This build works because it has 2900 toughness, and it has 3 invulns either for condi or power dmg. The heal skill the signet and berserkers stance counter condis, and endure pain the heal skill, and your traited endure pain counters power dmg.
The build is good because : It is a hard target to go after, it has a lot of cleave, it has a lot of dmg, it has mobility, it has rampage, you can stand on point, adrenal health sustain.
The build is bad because : It doesnt win 1v1s, moa hurts bad, teamwork is needed to use 100 blades.
Definitely have fun trying this out!
Engineer | Mesmer | Thief