I don't like building Vi as a tank. I just don't. She is far better applied, in my opinion, as an unstoppable bruiser. Her burst damage through Excessive Force, her excellent engage with Vault Breaker, and just generally massive Attack Damage scaling allow her to snap onto her target and secure the kill long before the other team has time to react.

Vi specializes in extreme damage. Her heavy AD scaling on all of her abilities makes her an extremely powerful assassin.

Pros:

High Burst Damage
Excellent Chase
Amazing AD Scaling
Free Initiating Barrier
Extremely Powerful Duelist
Decent early ganks


Cons:

Only Physical Damage
Doesn't Tank Very Well (Which is sometimes required in a Jungler)
Very Single-Target Oriented
Easily shut down by Crowd Control

Your first choice for Spells will definitely be Smite. You really can't jungle in early game without it. Plus, in late game, if you're team isn't doing so well, 1000 True Damage to an enemy Super Minion is always nice to have lying around.

For your second slot, you've really got two choices. Flash or Teleport.

In most cases, or especially when your opponents have a lot of move-speed-oriented characters, Flash can help you either snap onto an enemy that's just out of range, or combo with Vault Breaker to disengage from a fight fairly easily. A great combo is: Activate Vault Breaker to begin charging. When it's full, Flash toward an out-of reach opponent. Vault Breaker into them to commence the damage.

Alternatively, if you have an ally that is either really good about placing wards (Typically your team's support) or places lots of permanent items in semi-random places (Read: Teemo's Noxious Traps) Teleport definitely helps you easily set up ganks from nearly anywhere on the map.

For Vi, Greater Mark of Armor Penetration is a must. All of her abilities deal Physical Damage, so do everything you can do to maximize the effect of her AD items. 12 Armor Pen is nothing to sneeze at.

Also, Greater Seal of Scaling Armor provides a small boost early on, but grows quickly, passing it's flat counterpart at level 6, and helps her late-game survivability.

In the same vein, Greater Glyph of Scaling Magic Resist makes it safer to gank some lanes after 6, though you could also go with Greater Glyph of Cooldown Reduction, depending on your play style.

As far as Quints go, the choice is really yours. I like Greater Quintessence of Experience, but you could also go with Movespeed, Lifesteal, or more Armor, MR, or CDR.

For Vi, you're probably going to want 21/9/0. In Attack, focus on the Physical Damage tree, plus the Jungle extras. For Defense, you're going to want bonus health and the Jungle extras, as these will help you survive your first push through the jungle. Also, note, in attack, I choose Executioner and Dangerous Game over Spell/Blade Weaving, since, despite using her abilities(borderline-spamming) the ability to clean up champions after they get down to 20% health, as well as gaining back some of your own health afterward is far more in Vi's best interests.

When playing with Vi, Attack Damage Scaling is the name of the game. All of her abilities can get crazy powerful if you stack on the AD.

Starting Items
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Like any good jungler, you'll want to start out with Hunter's Machete, 5 Health Potions, and a Sweeping Lens as your Trinket. The Machete helps you clear camps, and the Health Potions let you stay in jungle for quite a while on your first go. I get Sweeping Lens to help with ganks, usually, as by the time you're ready to gank, the laner will have likely dropped a Stealth Ward in the bush by their lane. While the Sweeping Lens won't make your gank any easier if they did, at least it lets you know they can see you coming.

For Vi, if you follow the prescribed jungle path (See Below), you should have enough gold when you back for the first time to buy Madred's Razors, Boots, and 5 more Health Potions (Minimum 775G, for no potions, or 950G for all five.) For Vi, with the bonus damage on every third hit, Attack Speed is your best friend.


Bruiser Core
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Your Madred's Razors will build into a Wriggle's Lantern, and the Boots into Ninja Tabi. Wriggle's Lantern (Or, more importantly, Feral Flare) is an especially potent item on Vi, once you hit the 25 large monster/kill/assist zone. The bonus Magic Damage will ignore any armor your targets have built, varying your damage output. Furthermore, later in the game, when you can take a camp in about 1 second flat, it can accumulate stacks quickly, slowly increasing the bonus magic damage.

Ninja Tabi are more from personal preference. They grant you an Armor bonus, which lowers the damage of all jungle creeps, and the passive reduces all basic attack damage even more, making it more difficult for an AD champion, especially an ADC to kill you before you kill them. Even better, the passive scales with their damage.

Trinity Force is arguably one of the best items to build on Vi, due to the sheer utility of all the different stats it increases. Rage grants you a movement increase whenever you land an autoattack on an enemy, helping your chase, and Spellblade gives you bonus damage all the time. Okay, not all the time... But, when you activate any abilities, it procs Spellblade again. Did you just Vault Breaker into an enemy? Your next attack deals Spellblade damage. What's even more entertaining is that Spellblade triggers when you activate Relentless Force, not when you connect with the excessive autoattack. So, rather than dealing 115% AD + 70% AP, you're dealing 115% AD + 70% AP + 200% Bonus AD to the thing you're attacking. Every Attack Damage item you build further increases this crazy damage. The Zeal aspect of Trinity Force is a marginally less useful, but the Movement Speed and Attack Speed still definitely help. So, when building Trinity Force, follow this path: Phage(1350G)--> Sheen(1200G)--> Zeal(1175G)--> Trinity Force(3G). (Note, you'll likely actually skip Zeal entirely, as it takes you about 1 second longer to get the 3G it requires to upgrade it all into Trinity Force

As an aside, if you're having trouble sustaining, because maybe there are 2 tanks on the other team, or the enemy jungler keeps invading you, forcing you to back after you fight them off, you might want to grab an early Vampiric Scepter between Phage and Sheen. Don't worry you'll use it pretty soon.

Attack Damage
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You need two of these.

You can take your pick, but I usually go with Ravenous Hydra and Frozen Mallet, but I'll explain each below.

Ravenous Hydra: In most cases, the Hydra will be the first item you build after Trinity Force. Get the Vampiric Scepter, followed by the Pickaxe and Longsword, and if you've got an extra spot, one of the Rejuvenation Beads. 99.9% of the time, this is the best solid AD item to build on Vi. It gives you Lifesteal, AoE damage on your autoattacks, and some extra health regen. Not to mention it's active, Cleave. It helps you quickly clear both jungle camps and waves, as well as basically giving you another free autoattack that you can activate between your other autoattacks, sending your burst damage even higher.

Frozen Mallet: For me, the Icy passive alone is enough motivation to get this one. With a 40% slow applied whenever you autoattack or Vault Breaker someone, most of the time, no one can escape you. Plus, a nice bit of Bonus AD, and a large chunk of HP (700 to be precise) increases both all of your abilities, as well as your general survivability.

Bloodthirster: I don't usually buy this, unless I'm snowballing so hard I don't even need any defensive items. While the stacks are really easy to accumulate, and the bonus Lifesteal is great, the AoE and active on the Ravenous Hydra is usually enough to keep my thirst for blood sated. (See what I did there?) That said, it does (when fully stacked) have the highest Bonus AD stat in the game (Except a near fully stacked Sword of the Occult but that's really hard to do...).

Black Cleaver: This is a decent alternative for the Frozen Mallet, and I'll usually take it if the enemy is building a lot of armor, especially if they have two or more tanks. The armor shred is great, as it actually reduces the enemy's armor, allowing your ADC or any other attack damage champions to deal more damage. And, of course, extra Attack Damage, Health, and Cooldown Reduction are always useful.

The Last Whisper: This item is generally not necessary, except against one specific champion: Rammus. If you're facing a Rammus in the jungle, the Last Whisper will significantly increase your performance.


Defensive Items
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Since you're a bruiser, you won't build many solely tanky items. You'll usually only need one, but which one you build is determined by what opponents you're facing.


I usually build Guardian Angel, but as before, I'll explain them all below.

Guardian Angel: This is, in my opinion, the best tank item on Vi. It gives decent Armor and Magic Resist, but the passive is by far the most awesome. Even if you don't survive your initial dive into the enemy team, the 4 seconds is usually long enough for your cooldowns to refresh, letting you either Vault Breaker out of the fight, or if you're lucky, snag another kill.

Randuin's Omen: If your opponents are mostly AD, as in 4 of the players deal primarily Physical Damage, Magic Resist typically won't be as much help. So, the extra Armor, as well as a nice slice of HP helps you survive even a high-shred ADC. Plus, the active gives you even more chase ability.

Spirit Visage: If the enemy team, however, is primarily Magic Damage, especially if they have an APC instead of an ADC, Spirit Visage is an excellent choice. Magic Resist, a chunk of HP, and some awesome CDR and life gain effects make it a solid choice.

Warmog's Armor: There is only really one place you'd need to build a Warmog's Armor instead of any of the above options, if the entire opposing team has already built decent amounts of Armor/Magic Penetration. If every opponent is sporting Black Cleaver, a Last Whisper, a Void Staff, and/or Liandry's Torment, build more Armor or MR to counter them isn't going to be as effective.


Boot-chantments
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Furor: This will be your go-to on Vi most of the time. That 12%, plus the Rage passive on Phage/ Trinity Force will put your movement over 500 any time you smack someone. Throw a little Icy in there and no one will ever escape you.

Homeguard: Most games you'll only build Homeguard if your team is losing rather handily. The significant increase to health gain while on the fountain, as well as the quick movement back into the base/fight can turn the tide in a losing battle.

Alacrity : Usually a poor choice for Vi, as she really needs the extra movement to chase, rather than just move around. At full build, her movement should be at 424 base, with the soft movement speed cap reducing the bonus from Alacrity to only 16 points.

Distortion: Like Alacrity , this enchantment really isn't a good choice on Vi. With Vault Breaker, you aren't reliant on having Flash up to allow you to escape a sticky situation, and most of the time, getting Teleport a few seconds faster isn't usually going to help you out much, unless you're spending the entire game putting out fires in lanes.

Captain: What are you doing? Move along, nothing to see here. But really, Captain has, perhaps, one slightly useful application on Vi. If your team doesn't have a tank to engage, the slight movement speed increase to your allies approaching you after you engage a team fight might help swing it in your favor. In all other situations, ignore this enchantment entirely.

For your Skills, you're going to want to grab Denting Blows first level, but max it last. The 20% armor shred, attack speed buff, and bonus damage on every 3rd hit helps you clear jungle camps without burning through your potions so quickly. Plus, the bonus damage scales with youropponent's maximum health, dealing an extra 4% at first level, and growing up to 10%, plus another 1% for every 35 points of Bonus AD you've built.

Next, take a level in Relentless Force, as the AoE damage can strike every creep in a camp. As it builds up to two charges at a time, and it increases your next a bit of flat damage, 115% of your AD, and even 70% of your Ability Power. You can even use it to tag fleeing champions through minion waves, as the explosive damage spreads out to 600 range behind your original target. Furthermore, triggering the ability resets the timer on your autoattacks, letting you get off the 3 hits to trigger Denting Blows really quickly.

At 3rd level, Vault Breaker is your best choice. Your primary engage, Vault Breaker will be the first skill you max. You can use it to jump most jungle walls, often mitigating the need to burn a Flash to escape an enemy champion. You'll take it whenever you can, maxing it at level 9. As an alternative option, you can also start charging Vault Breaker, then ,once it's at maximum charge, Flash toward a fleeing enemy to ensure you connect. In the late game, with a base cooldown of only 8 seconds (Less if you've built any CDR), it makes Vi a powerful chaser, or even just really good at running away. One other note, Vault Breaker will also apply spell effects to everything you hit with it, adding a stack for Denting Blows, Icy, Spell Vamp or whatever else you've got. (Note, it applies these as an AoE ability, reducing the overall effectiveness of said effects.)

Of course, for your ult, Cease and Desist, you'll level it up at 6, 11, and 16. It deals amazing damage, as well as knocking up whoever it hits, and making you immune to any Crowd Control your opponents try to stop you with. Only effects that make the target untargetable can interrupt this ability, as Vi will chase them through walls, minions, even other champions (dealing 75% of its damage) to slam them into the ground. However, watch out for Spell Shields like Morgana's Black Shield or the passive on Banshee's Veil, as they will completely block the ability.

Your E, Relentless Force is your second max, as the massive damage you deal will both shut down enemy champions, as well as everything else anywhere near them.

Finally, while not the most spectacular skill ever, your W, Denting Blows, will both buff your attack speed, as well as shredding your opponent's armor, and dealing some extra bonus damage every third hit.

And let's not forget her Passive, Blast Shield. Whenever Vi activates one of her abilities, you gain a short bonus health equal to 10% of your max. At full build, this amounts to about 300 bonus health, not quite as strong as a Barrier, but still quite solid. This is a great ability on a jungler, especially early on, as it's cooldown is typically longer than, or at least very close to, the time it takes you to walk between jungle camps. And, late game, with a Cooldown of merely 8 seconds, if you're forced to flee, it can shield you every time you use Vault Breaker.

Vi is geared toward eliminating high-value targets quickly. Locking onto an enemy Carry or High-Damage Midlaner with Cease and Desist both plows through most of their team, but also allows her to quickly burst down said Carry, with a Vault Breaker open if they try to escape. If you build her with a few tanky items, she can also serve as an Offtank in 2v2s or 3v3s, charging in and absorbing damage while your Mid or ADC shuts them down.

Vi also has a nearly unbeatable dueling capacity. Catching an enemy out alone almost guarantees a kill, against all but the most tanky champions, like a Dr. Mundo or Volibear stacking Warmog's Armors.

For ganking, Vi has high burst damage, as well as a solid engage. In most cases, you'll want to come from either the side or behind your target, as the knockback on Vault Breaker will make it easier for your laner to get more damage on their enemy, or at least make it more difficult for them to flee up to their turret. If your laner is behind in kills, your team can often be helped by letting them snag the kill and gold. However, if they're getting a bit fed, or if their opponent is (sadly) on a killing spree, you do need that gold too. The kill gold, plus their bounty will help you snowball a bit, putting you ahead of your jungle opponent. Don't get mad if the laner last-hits your gank target. They did their job too, and you can always kill someone else, somewhere else. Remember, Assists net you gold too, especially if you have more assists than kills.

Of course, after you've taken down the enemy laner, you're often in an optimal position to push the lane. Vi's waveclear abilities with Relentless Force and Denting Blows are superb, and you can help the laners shred down their turret some while their opponent is busy being dead.

Personally, when I Jungle with Vi, I level Denting Blows and grab the Lizard Elder first. The Blessing of the Lizard Elder nets you both a slow (Which is less useful), and a bit of bonus True Damage. When you finish, your autoattacks will land an extra 12 damage burn (24 damage total), helping you polish off the early jungle camps. As long as your leash didn't accidentally snag some of the XP, you'll also level up once, taking a point in Relentless Force, and probably use one potion (If you're on blue side, and have a support with a heal, you might not even need to do that). When you attack, focus the Lizard Elder first, with your leash. Be careful to warn (Alt-click) them if they're sticking around too close to Smite range.

Next, you'll want to head to the four Wraiths. I usually target the Lesser Wraiths first, landing Relentless Force once, and you can knock the first down in exactly 3 hits, triggering the passive on Denting Blows, and increasing your attack speed to defeat the other two quickly. Save your second charge on Relentless Force if you get one, and it will help you later. You'll proc another potion here, or if you were healed on first camp, your first.

Then, roll onto the Wolves. Unlike Wraiths, you want to target the Giant Wolf first. Go something like this: Autoattack, Relentless Force, Autoattack (Triggering Denting Blows), repeat. Here, you want to lead with an autoattack, drawing both the smaller creeps in before you smash them all at the same time. You'll probably proc another potion here.

Once you knock out the Giant Wolf, and both his little minions, you head for the Ancient Golem. You should have 2-3 Health Potions left, plus over half of your health. Charge straight in, proc at least 1 potion, and use the same combo as above to burst down the Ancient Golem first. Hit it with Smite as soon as it get's down below the 410 health mark. If you did it right, you should be able to clean its Young Lizards out while still healing from your pots. Make sure you level your Vault Breaker here, so all of your non-ult abilities are at level 1.

Now, you have a choice. Take a look at Top and Mid or Mid and Bottom. If one of the lanes you're close to is getting pushed, you just leveled your ganking engage. Signal the lane you're heading too, run down and hit the usual ward bush with a Sweeping Lens, right when you enter it. If they forgot to ward against you, ping the one you want to smash with a Ctrl+Click, and run in. Smack them with your Vault Breaker, then use the same trick you used against the jungle monsters, though this time they already have one stack of Denting Blows, just autoattack then Relentless Force. This quick burst will shred most of whatever health they have left, though if they've managed to survive this, they're probably running. Vi's base movement speed is 350, faster than most champions, except the infamous Master Yi, so you shouldn't have trouble chasing them. However, don't hesitate to Flash ahead of them if they're looking like they'll escape.

If both your close lanes are pushing, or at least frozen, head back to Wolves. They'll have respawned by this point, letting you kill them again. If you have about half of your health left, or more, go after the Wight. Warning: trying to take Wight this early can be pretty risky, so make sure you have Smite available. Again, if you magically have about 200-300 (Or more) health, go crush Wraiths again before finally backing. However, don't overextend yourself. If you feel the need, go ahead and back a bit sooner, rather than risking an Execution. (Not technically a completely bad thing, but definitely looks bad to your team.)

After this, you should be able to afford both Madred's Razors and Boots and a couple more Health Potion, and you've pretty much got free-reign to take camps in whatever order you see best. However, always make sure to grab your buffs whenever they're up.

Finally, Once you finish Wriggle's Lantern, Ninja Tabi and maybe Phage and/or Vampiric Scepter, you should be at about level 9. You've now got the staying power to solo the Dragon. If you can see the enemy jungler in top lane, you can pretty safely attack this giant monster. Blessing of the Lizard Elder definitely helps, but it's not exactly necessary. Remember to save your Smite until it will 1-hit the Dragon to avoid getting it stolen. As an alternative, once you have Wriggle's Lantern and the Ninja Tabi, as long as bottom-lane is pushing well, you can ping them for help and take Dragon a bit sooner.

In the mid game, Vi's high burst damage makes her an awesome counter-jungle as well. If you feel up to buying a few Stealth Wards (You'll likely want to save the one from Wriggle's Lantern for the Dragon), you can drop them at your enemy's Red and Blue camps, and invade them whenever it's fairly safe to do so, denying your evil opposite valuable XP and buffs.

In the late game, nearly all jungle camps, except Dragon and Baron Nashor become laughably easy, as Vi can flatten them in just a few seconds. Even Dragon can't last long against a high-leveled, properly equipped Vi.