One of my favourite mon last gen was golbat as it was probably the best user of my favourite combination of bulk+decent speed+recovery+taunt. Now that pro-bat and serp are in the higher tiers, vigoroth, murkrow and servine remain as the only mons capable of using this combination in NU and vigoroth stands out as it's best user to me.
Vigoroth @ Eviolite
Ability: Vital Spirit
EVs: 196 HP / 88 Def / 224 Spe
Jolly Nature
- Double-Edge
- Toxic
- Taunt
- Slack Off
Speed, bulk, taunt and recovery together make a very effective combination as if an opposing mon is not 2hko'ing you, outspeeding you or is named xatu, it's simply not killing you regardless of it's recovery and set up options. Now in this case, you have to add knock off to the balance because you rely a lot on your item to take attacks but considering vigoroth only has one weakness to fighting and that most knock off users also carry a fighting move anyways (especially if sneasel get's banned) it's not that bad of a flaw.
The set is optimized to outspeed max speed rotom-s and everything slower as getting a speed tie with base 90 speed is not very useful and the extra EVs can be used a lot better in additional bulk. In fact, with the listed EVs, you shouldn't even have a problem with tauros as long as you're hazard free. Indeed tauros's rock climb is probably the strongest physical non choiced, non boosted and non fighting move you'll encounter on a regular basis and it only has 2,3% chance of 2hko'ing vigoroth (1,7% when you consider the possibility of missing). Considering rock climb is bound to miss at least once (85% acc), you should be able to get a toxic in and stall out tauros for a couple of more turns.
Fighting types apart, all you need to worry about on the physical side are poison types that can't be toxiced and can poison you even through taunt and klinklang who even if it can't set up will just never die to double-edge as long as he's got lefties. Still, these guys aren't that annoying mid game since you can just taunt them and switch out.
It may seem like that's still quite a lot of flaws but considering
you can actually sweep late game with a mon that can be used defensively throughout the battle and without even having to set up, vigoroth still has a lot of good points going for him, he's not even frail on the special side (219 s.def with evio and 350 hp), he just fears the scald burn and s bomb poison.
For pairing, I'd suggest garbodor as he can handle fighting types and klinklang pretty well and set's up spikes on taunted opposing garbodor (or other poison types). Guts AV hariyama is also a cool partner since he can take knock off, some big special hits as well as scald and s bomb very well for vigoroth.
couple o' calcs
252 Atk Life Orb Sheer Force Tauros Rock Climb vs. 196 HP / 88 Def Eviolite Vigoroth: 149-177 (42.5 - 50.5%) -- 2.3% chance to 2HKO
252+ SpA Mesprit Psychic vs. 196 HP / 0 SpD Eviolite Vigoroth: 150-177 (42.8 - 50.5%) -- 1.2% chance to 2HKO
(since you outpseed mesprit, the fact he'll never miss psychic is irrelevant to put in a toxic if you come in with full health though a crit or sp.d drop is bound to happen)
252 SpA Vivillon Hurricane vs. 196 HP / 0 SpD Eviolite Vigoroth: 151-178 (43.1 - 50.8%) -- 3.1% chance to 2HKO
(if you ever consider switching him in to take the sleep powder)