Pros:

- Very Cost efficient, its very cheap for very strong passives or actives
- You are still very tanky because of Soul Furnace (W)
- You gain an shield when you cc, when W is on cd you can survive the cd with Fimbulwinter
- Font of Life will give your teammates a bit of healing, which also scales with Revitalize.
- Revitalize empowers you W, Font of Life, Knights Vow healing and Fimbulwinter.
- Glacial Augement is a very good tool to secure and additional q or combos with your Teammates. It also reduces the damage taken, when the enemies are standing in it. Glacial Augement also stays for a long time because of your ult and q.
- Magical Footwear spares you and additional 300 G
- Cookies will help you survive tough match ups and also grant max mana, which scales with Fimbulwinter
- Cosmic Insight ( can be replaced with Impaired Movement) helps you to switch your actives (Knights Vow and Anathemas Chains) more often and will enable you to use Exhaust every 177 seconds instead of 210 seconds.
- Anathemas Chains will make you tankier against the enemy carry and will reduce their Tenacity, which will secure an ult and q combo nearly every single time.
- Knights Vow will make your chosen carry a lot tankier
- Is very team friendly
- Your cc can hard carry a team fight with ease
- Can even help monkeys to carry a game wow.
- Is fun to play
- Tower diving with 1,2 k Shield is easy
- Junglers will love ganking you for free kills, because your e will enable a easy engage on the enemy laner
- Roaming is easy because of 900 movement sion ult, which deletes enemies health bars
- Warding is basicially useless against a roaming sion

Cons:

- Is very Team oriented, which in itself isnt bad, but if your team is bad, you can kiss your *** good bye. But most builds will suffer this Con anyways
- Is a bit defensive
- Relies on clearing a wave as fast as possible (for roams), which is easy because of your spell combo, but you are very "vulnerable" while doing so.
- If your bot lane goes 0/20 you will be blamed, even though you gave top lane a huge lead and got herald for your team.
- If your top lane goes 0/20 you will be blamed, even though you gave bot lane a huge lead and got drake for your team
- It doesnt matter what happens you are the one to blame, but well support mains and jungle mains already know this feeling.

Survive, gain stacks and gold, wave clear as fast as possible with your huge damage spell combination, your mana pool isnt gonna drain as fast as it usually does, because of tear and cookies. Try to zone the enemy with your q so he does not get the money he needs for his core item, which costs at least 200g more than yours. The enemy laner will try to harass you as much as possible, which will lead to your farm advantage, because they think it is possible to kill sion in lane without punishment, show them that they are wrong. If your jungler decides to early gank you, try to hit your e for an easy engage on the enemy laner, for that you can cancel its animation with the second activation of w. The W also cancels the animation of Q, but its still visible and the last part has still an animation.

The laning phase is now optional (literally). Try to roam bot or top as soon as your ult is ready, push out your wave with your spell combo and then got to the river bush and ult down the chosen lane, especially bot for that juicy early drake pressure. Your early base damage will delete enemy bot laners as if they are pinatas. If you gank top lane it can lead to a huge lead for him, he will love you, because the island state, which is top lane, can still snowball without the enemies noticing it.

You now have Evenshroud and maybe Fimbulwinter. You will get a shield everytime you get ccd and cc. You will do an extra 9 % damage because of Evenshroud, when you cc or get ccd. You will reduce enemy damage by 15% and slow them if you hit an q, because of Glacial Augement. The damage diffrence will be 24% just for doing 1 Spell. Exhaust will disable the enemy carry, while you are either face hugging them or peeling your whole team (especially the carry). In the mid game you can decide, who you are going to bully, because there is no chance they will kill you in this life time.

You have now Knights vow and maybe anathemas Chains. This will secure you the win in most games. Knights vow will make you and your carry very tanky, Revitalize also bumps up its healing. Try to be the Engage tool for your team, you have 4,5 k hp you wont die unless the enemy carry is a vayne. Landing your ult even as a slow against 2 people will decide the team fight into an easy victory. Use brushes for traps (especially if there is a control ward inside). Anathemas Chains will reduce 30% incoming damage from the enemy carry and their tenacity by 20%, this secures easy spell rotations on them.

Its a lot of fun, if you are a sion main, you might enjoy this diffrent playstyle. Lethality is sometimes very hard to play, because of the gold costs or being out damaged by the enemy team. You also tend to die before getting any of your spells in. This build is super tanky and you will still have reliable base damage to back your cc up. Your team will have a lot of damage anyways most of the time.