Hi, this is my guide on how to play Vi jungle. Vi is one of the strongest junglers in the game right now due to her fast clear time, strong ganks, high mobility, objective control, and crowd control. Note that this guide is aimed at playing Vi as a damage dealer more so than a front line tank, so it's most effective to use her this way when you have someone else on your team that can tank for you.

Vi scales really well with attack damage and attack speed so I take a mix of these stats. Flat AD marks and quints are another alternative, but I find that the attack speed helps to proc more easily and armor pen scales well with it too.

Going 21/9 is a more damage focused set up and it helps Vi to duel as well as assassinate squishy targets. Taking Double-Edged Sword lets Vi deal 2% more damage while only taking 1% more. This is definitely worth it for an assassin like her. Taking Butcher and Feast makes her clear a bit faster and sustain better in the jungle. Both Fury and Sorcery are good on Vi. Fury directly gives her more damage as Sorcery will lower the cooldown on her spells and most importantly the cooldown of her ultimate so taking either one is fine. The rest of the masteries are pretty standard for an attack damage jungler.

(Passive) Blast Shield Cooldown: 18/13/8 seconds

Blast Shield is a solid passive that gives Vi a shield based on her maximum health. It only procs when you hit an enemy with an ability, so if you only have one ability ready and your Blast Shield has a one second cooldown, it can sometimes be worth holding off on using that ability until your passive is ready so you get the shield.

(Q) Vault Breaker Cooldown: 18/15.5/13/10.5/8 seconds

Vault Breaker is a short cooldown gap closer and crowd control ability. This ability does a ton of damage if you can fully charge it so always try to fully charge it if possible. Vault Breaker can jump over walls which can let you get around wards and come from unexpected places to gank.

(W) Denting Blows Passive

Denting Blows procs on every third attack on the same target, dealing %max health damage, reducing their armor by 20%, and increasing your attack speed. Vault Breaker applies one stack of Denting Blows, so it's really easy to proc by using Vault Breaker, one auto attack, and Relentless Force.

(E) Excessive Force Cooldown: 1 second Recharge Time: 14/12.5/11/9.5/8 seconds

Relentless Force is an auto attack reset that deals extra damage and damages units behind your target as well. The cooldown for Relentless Force begins when you cast the ability rather than when you attack with it, so activating it 5 seconds before you attack will allow it to come off cooldown faster.

(R) Assault and Battery Cooldown: 150/115/80 seconds

Cease and Desist is another gap closer and crowd control ability. It locks onto your target and causes you to follow them even if they Flash away.

Starting Items Hunter's Machete helps clear jungle creeps and upgrades to Ranger's Trailblazer later. Health Potion x2 help to sustain through the first jungle clear and help in early fights. Stealth Ward is good for scouting early game and can help to scout out parts of the map. I recommend switching to Sweeping Lens at some point because I feel that it is more useful after level 9 due to its one minute cooldown.

Ranger's Trailblazer Ranger's Trailblazer is the first item to rush on Vi as it helps her clear and sustain in the jungle and she gets a power spike from the Warrior Enchantment.

Trinity Force Trinity Force is a great item on Vi because she can utilize pretty much all of the stats that it provides. Her Relentless Force can proc the passive frequently and it adds to her burst. This is a core damage item on Vi and you should get it after finishing The Brutalizer unless you're very behind.

Hexdrinker Hexdrinker is a great item on Vi because it provides offensive and defensive stats with an easy build path. Get this item if the enemy team has at least one source of magic damage. Upgrade it to Maw of Malmortius later in the game once you are short on item slots.

Randuin's Omen Get Randuin's Omen if the other team deals mostly physical damage and you don't think you can survive fights without it.

Banshee's Veil Get Banshee's Veil if the other team deals mostly magic damage and you don't think you can survive fights without it.

(Early Game)
In the early game, try to gank as much as you can without falling too far behind. Look for opportunities to use Vault Breaker to jump over walls to pass by wards and sneak up on enemies. If you don't see any good places to gank, farming until level 6 is a good option as well.

(Mid Game)
In the mid game, use your ult to gank as much as possible. Make sure to buy wards to track the opposing jungler. If you know that you aren't going to get counter ganked, you can usually get a successful gank off by running down the lane and using Vault Breaker to get close enough to use Cease and Desist. Once you have The Brutalizer, you can do dragon really easily because of Denting Blows so look to secure dragon as much as you can.

(Late Game)
In the late game, you become a huge threat once you get Trinity Force along with Ranger's Trailblazer - Warrior and Black Cleaver. You can pretty much kill anyone 1v1 once you get those items so look for opportunities to catch and assassinate the other team then forcing objectives once you have favorable odds.

(Team Fights)
Vi is pretty versatile in terms of what she can do in a team fight. If you're tanky, you can initiate really well and kill off their back line champions. Vi can also peel for her own back line if needed because of the armor shred provided by Black Cleaver and Denting Blows along with her crowd control from Vault Breaker and Cease and Desist.

In conclusion, Vi is a very well rounded jungler who farms quickly, has strong ganks with her ultimate, and is strong throughout the entire game. She's not very mechanically intensive so I would recommend her to new junglers looking to improve! I hope this guide helped and have fun :)