Two peanuts were walking down the street. One was assaulted. Luckily, the other was wearing an Assault Vest.
Yes, I am the Assault Vest guy (and yes, I know that's not how Assault Vest works), so it seemed only fitting that I write an article on Assault Vest, as I've spent lots of time seeking out effective Assault Vest users. Not all of these sets are my own, I used some sets and ideas from others.
There are many misconceptions in competitive Pokemon, one of which is the proper use of the item Assault Vest. Assault Vest (AV) is a weird item. For those who may not know exactly what it does, it's a handy item that multiplies the holder's current Special Defense stat by 1.5, while prohibiting the holder from using any moves that are not attacking moves. Will-O-Wisp, Recover, and Stealth Rock are examples of moves that can't be used with Assault Vest. So what this means is that you can't use Assault Vest on a Setup Sweeper, Status Spreader, Hazard Setter, or any other Pokemon that carries a non-attacking move, which is good, because that prohibits walls like Blissey from holding it (Thank God).
Now to strategy. The main misconception of Assault Vest is that it exists to boost Special Defense on Walls to sky high levels so that the Pokemon can take more hits. This is not a good usage, as most walls need non-attacking moves. The main thing it does is pad Special Defense for Tanks or even in some circumstances, create a Tank. The main reason you don't want to invest fully in Special Defense with AV is because you don't have access to instant recovery; meaning that if you don't have enough power to knock something out, the Pokemon isn't doing its job. On top of this, AV lets you switch in and beat Special Attackers, which you can't do without some offensive presence.
By and large, you want to have a positive attacking nature that doesn't hinder what you're trying to do with your attacks (Quiet, Modest, Adamant, Brave cover pretty much all of these pokemon). In conjunction with this, you also need a Pokemon with a pretty good attacking stat, otherwise, you aren't going to be dealing enough damage to matter whether you live an extra hit. You generally want to invest into HP and the raised attacking stat, usually always fully. Rely on Assault Vest to raise your Special Defense. Of course, there are exceptions, so those will be covered.
A very important characteristic of an AV user is typing. A good defensive typing is almost always needed for an AV user, because they're designed to take hits. Taking super effective damage will negate any reason to use the Pokemon.
Another very good, almost necessary ability for an AV user is a recovery move. Obviously, moves like Recover and Synthesis can't be used with AV; I'm referring to recovery attacking moves, namely Giga Drain and Drain Punch (and the much more narrowly distributed Draining Kiss). These moves, when used with an attacking nature, allow you to hit opposing Pokemon, steal their health, and allow you to gain access to recovery in place of Leftovers or instant recovery moves, a huge asset to have for a bulky Pokemon. For this reason, the ability Regenerator works very well with Pokemon that use AV.
A very good option for an AV user, but one that's a little less necessary, is Knock Off. AV lets you come in and tank a special hit. Then, with Knock Off, you either cripple the special attacker or whatever switches in to take you on. It's a move that you can spam with little to no consequence, because despite it possibly being not very effective, the utility of getting rid of an item is more than enough to make up for the lack of damage.
One big thing to look out for is status. It's tough for bulky Pokemon to deal with, but can really wreak havoc with an AV user.
Now, I'm going to list some Pokemon that make great AV users, a few obvious and a few less so, and a few Pokemon that appear like they would make great AV users, but don't really perform for one reason or another. I'll also give example sets that would be good to run.
The Stars
Tangrowth
The premier example of an AV user, it seems like the GameFreak employee that thought of AV either had a picture of Tangrowth on their desk at the time or was eating spaghetti. High HP, Attack, Defense, and Special Attack, Tangrowth lacks good Special Defense and Speed. Well, Assault Vest patches up that Special Defense to a more than acceptable level. It's typing isn't great, but that is more than made up for by its other strengths. It gets Giga Drain (and it's STAB), Knock Off, the fantastic ability Regenerator, and fantastic bulk. It probably benefits more from AV than any other Pokemon; taking it from RU and making it great in UU and viable even in OU.
Tangrowth @ Assault Vest
Quiet 252 HP/252 SpA/4 SpDef
Regenerator
-Giga Drain
-Hidden Power Ice
-Focus Blast
-Knock Off
Not much to say about it, this is your quintessential AV user right here, with HP Ice to catch Dragon, Flying, and other Grass types on the switch, and Focus Blast to get past Steel, Dark, and Ice types.
Conkeldurr
Probably the best user of AV in the game. Drain Punch from a gargantuan Attack, good natural HP and Defense, and decent Special Defense. Knock Off, Priority, and a safeguard vs. status (Guts) make it so tough.
Conkeldurr @ Assault Vest
Adamant 252 HP/252 Atk/4 SpD
Guts
-Drain Punch
-Mach Punch
-Knock Off
-Ice Punch
Not much to say here either. Standard for a reason.
Tornadus-T
There's a reason this thing was banned from UU. This thing was a terror, hard to take down, and one of the best pivots in the game. It's got less bulk overall than Tangrowth, but has much more speed, and hits just about as hard. The only reason it doesn't top this list is that it doesn't have a recovery move like Drain Punch. It has a surprisingly good typing, and a fast U-Turn with Regenerator makes it so tough to catch and take down. Knock Off just makes it impossible to switch into. Any VoltTurn team would be smart to add this to their lineup.
Tornadus-T @ Assault Vest
Jolly 4 HP/252 Atk/252 Spe (whatever level, make the HP and odd number)
Regenerator
-U-Turn
-Air Slash
-Superpower
-Knock Off
This is one of those aforementioned exceptions. 121 Speed should not be ignored, and it needs attacking power, so HP is the ignored stat here. Which on something so fast, isn't too bad. U-Turn, 121 Speed, Regenerator, and great special bulk make Tornadus one of the best users of Assault Vest, and possibly the best VoltTurn candidate in the game. Air Slash is used on this set because it doesn't really have a physical move that's better, and the 30% flinch rate makes it that much more annoying. Jolly is instead of Hasty because this is, above all else, a defensive pivot.
Snorlax, Tyranitar, and Goodra
These three kind of fit into the same mold. None of them have Knock Off, recovery, or Regenerator. But what they do have is Special Bulk and Attacking Power, and they have it in spades. Tyranitar hits like a truck, Snorlax has massive HP, and Goodra can run a very effective mixed set. The strategies for each are just a little varied.
Snorlax @ Assault Vest
Adamant 252 Atk/252 Def/4 SpD
Thick Fat
-Return
-Crunch
-Earthquake
-Selfdestruct
The EV spread is the weird thing about it. The reason for it is that your HP is already so high, increasing it increases your bulk at a lower rate; i.e., 63 points into HP has much less percentage impact than investing in a naturally lower stat like Defense. Your Special Bulk is boosted with AV, so the only relevant stat left is Attack, which you always want.
Tyranitar @ Assault Vest
Adamant/Brave 252 HP/252 Atk/4 SpD
Sand Stream
-Crunch
-Stone Edge
-Earthquake
-Fire Punch/Fire Blast
Sand and AV take care of Special bulk. The only thing left is to tear them apart with that 134 Attack.
Goodra @ Assault Vest
Brave 252 HP/252 Atk/4 SpA
Sap Sipper
-Outrage
-Power Whip
-Earthquake
-Draco Meteor
My favorite Goodra set. Immunity to Grass doesn't seem like a huge deal with the resistance, but with a little prediction, it can win a game. Not only do you gain immunity to powder moves, but it makes a great switch in to any Grass type, because there's little they can do. Plus, it allows you to boost your attack, something you normally aren't able to do. Draco Meteor goes right by Physical walls that come in to tank the hit. A great partner for this thing is Rotom, it baits Grass moves.
Toxicroak
Bunselpower, you've lost your mind. How could something with a base 65 Special Defense be a tank? Not only is it one of my favorite Pokemon of all time, it has STAB Drain Punch, Knock Off, and a very powerful STAB move in Gunk Shot. But the biggest reason to use it is it's typing; this is a prime example of good typing winning out. Poison/Fighting is a wonderful typing, plus it gets Dry Skin, giving it, as a physical attacker, an immunity to Scald.
Toxicroak @ Assault Vest
Adamant 252 HP/252 Atk/4 SpD
Dry Skin
-Drain Punch
-Knock Off
-Gunk Shot
-Ice Punch
You know the drill by now. Drain Punch, Knock Off, Dry Skin recovery.
Donphan, Hitmonchan
Rapid Spin and Assault Vest go so well together. It goes well with an offensive spinner. Gives you that much more opportunity to Spin for the final sweep. Here are two sets that I like for these pokemon.
Donphan @ Assault Vest
Adamant 252 HP/252 Atk/4 Def
Sturdy
-Rapid Spin
-Earthquake
-Stone Edge/Knock Off
-Knock Off/Ice Shard
Most people look at Donphan and see a Defensive Wall. And rightly so, 90/120 is nothing to scoff at. But most forget it has a base 120 Attack with that great bulk. You have to choose between EdgeQuake/Priority, EdgeQuake/Knock Off, and Knock Off/Priority. Make the decision based off of your team.
Hitmonchan @ Assault Vest
Adamant 252 HP/252 Atk/4 Def
Iron Fist
-Rapid Spin
-Drain Punch
-Mach Punch
-Ice Punch
Kind of an inferior Conkeldurr that can Rapid Spin. Set is pretty straightforward.
Scrafty
Its defenses are already really high with a middling Attack, so it seems a little strange that AV would work here. But Scrafty is the culmination of several different factors that make it the perfect candidate to pull off a set that can only be done in 6th gen.
Scrafty @ Assault Vest
Adamant 252 HP/252 Atk/4 Def
Shed Skin
-Drain Punch
-Knock Off
-Dragon Tail/Ice Punch/Poison Jab
-Power Up Punch
You can still boost Attack with Assault Vest, just use Power Up Punch! Dark/Fighting is an incredible STAB combo. Drain Punch, Knock Off, PuP are all great. But the crux of this set is it's ability to beat walls with it's wonderful ability - Shed Skin. As long as you are patient and continue to boost your Attack and stay healthy, Shed Skin is going to make sure not even Burn can stop you. I like Dragon Tail in the third slot for fun times, racking up Hazard damage and also in case something comes in you don't want to face, but Ice Punch is also great coverage and probably the better option. I've seen Poison Jab before for Fairies, but honestly, you have no business staying in on a Fairy, so I don't really like it.
The Best of the Rest
Regirock, Regigigas, Vileplume, Armaldo. If you have a suggestion, let me know and I'll add it here.
The Dim Bulbs
Now we're going to look at some Pokemon that look as though they would have good use with AV, but don't really live up to the hype, whether for inability or availability of better options.
Avalugg
It looks like a prime candidate for AV. High Attack, unbelievable Defense, Rapid Spin, low Special Defense. But it's typing is the worst, and its Special Defense is so low, you can't leave it uninvested, even with AV, meaning you lose out of Attacking power. Plus, it has Recover, a move that should not be ignored. In short, it's really better as a wall, and should be used as such.
Forretress
Here's another; high defense, good typing, pretty darn good base 90 Attack, middling Special Defense, and Rapid Spin. It even has a few options for Attacks, including the momentum grabbing Volt Switch. However, Forretress has access to every Hazard in the game, and not using it for this purpose is really wasting the potential for a one-stop Hazard shop on your team.
Cradily
Sorry cmzoid, Cradily is unfortunately down here too. On paper, it should be good. Great Bulk, Storm Drain to give it an immunity and boosting option, Giga Drain, good mixed attacking options, etc. But it has a terrible typing, access to Recover - which is better than Giga Drain for the next reason - Low attacking stats. Base 81 isn't good. The health you steal is going to pale in comparison to just using recover and playing more defensively, plus it's a great Stealth Rock setter. If it took 20 points from Attack and put them into Special Attack, it wouldn't be here.
Florges
I've seen this one a couple times, and it's just not good. Florges seems to fit the bill just like Goodra. And as far as stats go, this is true. But there are two things holding Florges back. One is movepool. It doesn't have very many good options. To force it to run all attacking moves is much more detrimental than the boost from AV. The biggest thing holding Florges back, however, is the fact that it gets Wish AND Aromatherapy. There are a handful of Pokemon that can do this, and Florges is on of the best.
Dragalge
I think I saw this one because people just don't know what to do with Dragalge. Once Adaptability hits, it may actually do some damage, but for now, just don't. Truthfully, with an attacking stat lower than 100 and no recovery, I think this is going to be more suited to a Specs set.
Boosting Sweepers
I didn't really know how to label this set, so I'll just make it obvious. There are several Pokemon that fit the bill as far as typing, Attack power, and the like. Gyarados, maybe Garchomp, stuff like this that has good typing, good bulk, and the ability to tank a hit or two. You do not want to ever use these with AV. Not because they wouldn't be effective, but because they have boosting moves. Dragon Dance, Swords Dance, these moves are too good to pass up on Pokemon such as these.
Thanks for reading this, I know it was a lot, but as AV is an item that can be used in many different situations, it took a lot to cover them all. It is my favorite item in the game. I tried to cover the main archetypes of Pokemon that benefit the most from Assault Vest. Of course there will be more, and I hope you guys will comment below and we can add to this list. It's such a cool and useful item, I hope this convinces someone to try it out on their team.
TL;DR - Use Assault Vest you lazy bum.
awesome surprise and a great improvement to the forum 
