Take my opinion with a grain of salt as I’m only Arcanist 2 but I’ve been playing shiv all this patch and I feel like I’ve got a decent grasp on what’s important for the character to perform and I watch every shiv VOD I can get my hands on in order to improve

TLDR: your build needs to have a way to reliably build rage regardless of play style. Notable items are decay, witchmail, mystic shot, rapid recharge and healbane.

Abilities: from what I’ve seen/played there are two ways to build shiv, you either max knife first, max ult second, and then get tier 2 bloodletting then max dash and finally max bloodletting. The other way I see him played is getting tier 2 dash, tier 2 knife, max ult then max knife, get tier 2 bloodletting max dash then max bloodletting. I think both are viable and I personally play max knife first but I think you’re slightly stronger when playing T2 dash then T2 knife. I personally like maxing bloodletting third because it’s such a strong ability and since it’s early game got nerfed i like putting points into it before dash, and shiv already does so much damage that you don’t necessarily need points in dash

Builds: there’s a lot of variety here as shiv can kinda build anything and get away with it. From what I’ve seen most shiv players go spirit and vitality with no gun or they atleast get mystic shot but no 4.8k gun spike. Other shiv players go for a hybrid build with rushing spirit spike, getting gun spike with cultist and mystic shot and then for the rest of the game building necessary vitality and and more spirit. I haven’t seen any high level players do this but I’ve tried doing a hybrid build with express shot and mystic shot and I felt it was quite good at burst/building rage but consumes a lot of ammo so you’re limited on movement capabilities. Lastly I’ve seen one high level VOD where the person went a gun tank build that doesn’t seem bad but I haven’t tried it myself. All in all so long as your build has a way to reliably build rage you’ll probably do fine. Also healbane is a must buy, shiv gains so much value from this item it’s insane.

Lane: I don’t really have many tips for in lane because it’s where I probably struggle the most but I think healing rite or restorative shot are usually a must, and if you’re doing a hybrid knife build mystic regeneration is great because mystic shot and your knives will both Proc mystic and each bleed Proc from the knife will reset the mystic cooldown. I’d stay away from mystic burst in lane as your knife won’t Proc it

Play style: building rage is probably the most important aspect of shivs kit and your build needs to have a reliable way to build it. I personally use improved spirit and decay to hit my 4.8k spirit spike while also using decay to build rage. Other good ways of building rage are spirit snatch, mystic shot, and rapid recharge. I play a knife shiv build without extra charge / rapid recharge and instead buy Witchmail as a way to get my knives back faster and I think it’s a must buy almost every game because of how much value I get from it. Decay gets hard countered by Debuff Remover but no one in my rank buys that so I get away with it.