Hello, I want to share with you my ranger and her heros build, I think this is the best one I've use so far, first you will need to charm pets for your heros. Because this is a build where you pets act as your melee or meat shield. The basis of this build is to spread as wide as possible poison to as many foes as possible in the shortest amount of time. Sending out pets properly can help achieve this. I've notice, caster will often cast on Devona, cos she run the fastest, when pets goes into range they will be targeted next, leaving you ample of time to quickly spread around the poisons.
I basically tested this outside Doomslore and Eyes in normal mode sorry I was excited to share and failed to mention its for NM, so there are Charrs, mandragor, pine, imps, whisp, Avalanch and elements, the ocassional wurms are easy.
First thing first, basically you have to lay down and keep all the necessary spirits and preparations up at all time if possible.
whisp: target the closest. Easy, kill first one then the next and the next
the imps: target the closest using "\". While your h/h is on the first target, quickly tab and infect the second imps interrupt if its casting maelstorm, quickly switch back to the first target using this "\" so h/h won't change target, poison arrow it once more even if its already poison lol 5 energy won't kill you, then quickly tab tab (twice) to the third target infect it, or interrupt depending on what skill it is using, then switch back as before, because we want to disable as many maelstorm as possible.
Avalanche: must kill this first, you cannot poison these, just keep interrupting, it'll die pretty fast, and this is where pets comes in useful, Avalanche will use its shatterstone on pets instead of you and your h/h, if you are fast, using tab and "\" you will be able to interrupt it. (trick, is unfortunately if you have less then 50% health, its useless to run lol, so do not run when you get hit by maelstorm, running will stop Mhenlo and Lina from healing you, because they run too, and while running they can't heal, hence everyone dies, stay calm in the same place and wait it out, if you have above 50% health, keep fighting, Mhenlo and Lina isn't all that bad)
When there are 2 Avalanche in a group switch back and forth between them to interrupt what ever skill they try to cast, most take long casting time, so its pretty easy to interrupt.
Mandragor, kill the necro first if possible, and stay alert, as these uses traps, interrupt them as they like to burrow to you and lay their traps.
Charrs,
1) all ranger charr group - let hero work on one while you tab and "\" to infects the others
2) ele + monk + mesmer + necro + ranger + warrior + group - kill in that order. interrupt ele 2x firestorm and meteor, if it does not dies (it should in my test) you go on to monk, cos meteor takes long to recharge once interupt) if it dies, don't go to monk, you switch to mesmer/Dominator, because they ressurect, if you take down the ele and the mesmer, the rest are easy. take down the monk, then the necro, the ranger, then warrior. If you take down monk, then switch to Dominator/mesmer, to interrupt the res, quickly switch to ele cos i think they res too, while the h/h is on the mesmer.
Please give me feedback as to how this can be improve, especially on the mesmer, a good discussion is always welcome.
Choice of Hench are: Zho, Devona, Mhenlo and Lina (this is while i am in EotN, where Zho is an interrupt ranger, in places where Zho isn't an interrupt ranger you take Deaman I think he is the interrupt ranger in the Jade sea area. Take Cynn elsewhere, wherever shes available. )
Your Ranger character uses this [build=OgATcZMm1hyoaeM+Wsjvx0sZAA]
Ranger hero uses this [build=OgATYHMn5hy0bfNqmnTxx3sZAA]
Necro hero uses this [build=OAJTUYzaNapqKANQNIBE4azoqCA]
Mesmer hero uses this [build=OQJUAUBPQrIuNHMDFBRkBbmAAA]
Always take heros that have the best equipments.
Ressurect skill is not included in most of the above build. If you want to pack one, change your rangers build to Monk Secondary and bring Rebirth, replace the one you think is the least useful, for instant, lightning reflexes on Margrid.
I am going to test out something with the splinter and epidemic, will update the build when I have them tested.
And i think I should test some more

Anticipated Question:
why so many interrupt: its a by chance discovery, all the foes basically can't cast anything with this h/h build and dies pretty fast, I suspect the AI sometimes goes off and interrupt other foes that you did not command them to target. time the foes dies is a comparison between using my ele with 2 necros nad gwen, and this one kills roughly 40% faster, I did not time myself, its a feeling from experience. so...
why so many poison: i use another build where only the necro heros has rotting flesh and poison stuffs and the successful kill times is relatively slower. so i think the many poison arrow must have help. I switch to glass arrows while Ranger Hero have incendiary + concussion, taking out both poison arrow from myself and Ranger Hero. It could also be because I am more use to using poison arrow hence the effectiveness.