Pros
-CC for days
-Plenty of hp (end game)
-Peeling like a mad man
-E,smite>Q and they can't move
-End game, true damage is nothing
-Unstoppable

Cons
-Lots of hp at endgame, but lacking earlygame
-Pre 6 ganks can be difficult
-Knowing when to ult and how to steer
-Early-Mid game true damage hurts

Gromp>Blue>Red, typical really, smite that gromp

I go Stalker blade because his already excessive CC, get's ever more redonk, especially with omens, and I upgrade it to cinderhulk fairly late as the hp is helpful but isn't always great until, later on

Alas, Ranger's Trailblazer although helps clear time isn't such a hassle if you play Sion right, Skirmisher's Sabre is useless with this build it's effectiveness scales with atk speed, we don't have atk speed

His abilities used right are usually enough to clear camps safely, counter janglin' isn't recommended unless you have lots of vision, preferably if you know where their jangler is

W while charging Q, E large minions (Smite Gromp), detonate W asap pre-6 as it won't last, afterwards it don't even matter, auto then Q straight after for maximum effect

Sion can be a bit mana hungry early on, sometimes I take first 2 blue, but I always offer

When you gank E,smite>W>Q>W and let your team kill them, the hp bonus is the same from kills and assist as well as large monsters

Movement speed quint's, plus 3 points in utility help with typical getting around, boots of swiftness (+Distortion) and ghost makes chasing an ease when out of lane, Zz'Rot help with movement in lanes, also control scuttle crab, as with use of ult, well...

Usually, I'll ult from where the scuttle crabs are and move in a hook fashion, example move toward the enemy turret side and move closer to middle of lane, if you hit the champion then full charge Q right away, they'll either flash or probably die

When entering a lane, E a minion into them and follow up with smite, they won't be able to escape easily

W first for that sweet sweet hp, then Q to help clear blue, then max E for better slow and more effective ganking, Ult as you get it of course, then max Q for damage lastly with W

Most cases you'll enter with E if they're too far/fast smite then Q, otherwise smite after the stun from Q wears off

Whenever peeling, ganking or teamfighting make sure you have your shield up as you go in

Defense and scaling stats as he is an end game champion, as the match progress's his tanky capabilities scaling even more so, and due to his W's permanent hp gaining passive he can get more effective health from extra armour/magic resist while still having a bit of hp

Due to his melee nature and rather short range, chasing and tanky is a must, you have to catch up to them and you have to stop them in their tracks, being Sion is usually enough, blue smite and Omen's makes that even more potent, on top of various movement enhances

With this build, typically, you'll have roughly 350 armour, 250 magic resist and around 5,000 health at full build, you stand at the front and peel, and engage/chase/poke with E, pulling off a Q can cause your team to focus down on that target so make it count, not to mention you can Q multiple people, even a whole team, if they're going ham it can work to your favour

Ideally, you'll want to build up (On W's Passive) about 450hp around 15-25 minutes, 650hp at around 30+ and 800-1000hp after 45 minutes, if it lasts that long

CDR does help but isn't crucial to being an absolute CC-ing juggernaut, so don't fuss about going either Frozen Heart OR Thornmail