Welcome to the cheesiest support build in the game. Super tanky, doesn't require much skill and allows you to screw up massively with few consequences. As Tragoul's Corpse Lance Necromancer is the highest single target damage dealer, the question is what can you pair with it to maximise potential in groups. The 4 player meta is pretty set, but 2s and 3s still has room to work out what the best combo is. This zDH is one possibility.
Currently we are rank 1 NA having done a GR114 with para less than 1800. zDH is super tanky, so it can be played with low para at very high levels. I could easily see a pair with sub para 1000 doing 105+. We did the clear on xTonyJ's Twitch (https://www.twitch.tv/xtonyjdota), and will try to link the vid here once its posted to YouTube. The pairing will be much more competitive in season, as it is hard to see a zDH competing with a para 4000+ WD.
You are there to buff the Tragoul Necro's damage and toughness, and to provide a meat shield with your pets. So everything is designed around keeping up with the necro, buffing the necro and staying alive yourself.
In paragons: no Area Damage, max IAS and CDR then just get toughness.
On Gear: try to get 33% + CDR, then try for 62.5% + RCR, the rest into toughness. Some extra IAS would help, but isn't essential - ideally you'd have it on the bow, but I haven't found a decent bow yet, so it just has RCR, CDR and disc. Extra discipline is also very helpful (only allowed me to put max fury not disc), as is pickup radius.
NB. Zoey's secret is huge toughness, so make sure it is a 9% affix roll.
For 5th passive perfectionist is the best option, though I have been meaning to experiment with Thrill of the Hunt
You provide toughness by the sentries and numbing traps procs. So spread the sentries out where the necro is going to want to stand, and cast mutishot to proc numbing traps every few seconds. Don't vault through elites as that will stuff up the necro's Frozen lands stun, so in the lead up to the cycle you have to walk around and not vault. Too many vaults and the necro will be vulnerable as mobs won't be frozen.
Once cycle is about to happen make sure the elite has entangling chains on them, and marked for death. Wait till the necro is in cycle to proc wolf companion, otherwise the Taunt on boar will CC mobs. The necro will proc and occy by killing a trash mob, then vault through the elite to proc strongarms. Gather globes and move on bouncing from elite to elite. If you have a pylon don't hit it immediately, try and time it for what will be most advantageous (usually a few secs before cycle).
This build also works in 3s, but it really depends on what the 3rd hero is as to how to play. We've done a 112 with WD, zDH and trags and a 114 with zmonk, zDH and trags. Playstyle with monks is similar to 2s, with WD though you play a lot slower and try to kill large trash packs with the WD.
GL, happy hunting and enjoy bringing a new hero into the 2s/3s meta.