Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
I find that 2 dorans rings are a must for AP Sion because of how fast he can go OOM(Out of mana). 2 Doran rings help a lot to sustain your mana.
For boots I almost 99 percent of the times use sorc boots for its magic penetration. Other option would be CDR Boots. I don't like the CDR boots on Sion mainly because he goes OOM way too fast to benefit from CDR boots. I almost never use but if you are having trouble from CC too much, Mercury Treads is never a bad choice.
I see a lot of bad Sions rush sheen to lichbane.
Lich Bane is very good on Sion but what is the point of doing extra 100 dmg on your next auto attack.
It's better to get some AP and then start building Lich Bane.
I get sheen after my 2 doran rings and start building a rabaddon deathcap for the AP.
I used to use mejais when I was playing Sion from 1100 ELO to 1500 ELO.
If you are confident about being able to stomp the other team and carry your team to victory.
This should what your build order should be.
2x dorans rings > sorc boots > sheen > mejais > rabaddon deathcap > lich bane
Using the Lich Bane
- The bonus damage you gain from Lich Bane's passive can deal immense damage to towers.
- When you are low HP, pop your ult and you will gain nearly 30-50 percent of your HP from one swing.
- After your team won a team fight and move onto get dragon or Baron, use your ult to heal your teammates.
- Flash -> Stun -> Lich Bane Swing -> Shield Boom = :D
You should get at least 1 point in enrage so your farm can rack up additional hp.
Note that minion kills using your shield and stun applies with Enrage's passive.
This doesn't mean you should max enrage first.
If you look at my skill order, some of you will notice that I do not get a point in my ultimate until level 16. I do not get a point for my ultimate at level 6 because I find that you rarely benefit from your ultimate early game as an AP Sion. It's better to get extra damage from your stun. In higher level/ELO plays, its uncommon to end up in a situation where you will pop your ult and have a melee brawl with your opponent. Because AP Sion has such a crazy burst, you should try wearing your opponent down with your skills and finish them off with a flash, stun, shield combo.
In my opinion flash is must for AP Sion because it can be used both offensive and defensive.
You can use flash to escape ganks and bad engagement.
Offensively, you can open up surprise ganks with flash following with stun and shield explosion.
I feel that summoner spells are usually personal preference.
I personally can't seem to play without ghost so I use flash and ghost.
Magic Penetration Reds x9 (Should be used with any AP carry caster)
Mana regen per 5 per level Yellow x9 (Sion's abilities use up a lot of mana.)
Mana regen per 5 per level Blue x9 (Sion's abilities use up a lot of mana.)
Cooldown Reduction per level Blue x9 (I like mana regen per 5 better)
Quintessances should either be
Magic Penetration Quints x3
Movement Speed Quints x3 (Makes it easier for you to land a stun on your opponent)
Mix of Magic Pen Quints x2 and Movement Speed Quint x1
During laning, you should focus on farming and feed Enrage's HP passive.
Most matches I play I always have more hp than anyone on my team only having 2 Doran rings for additional HP.
When you hit around level 10-12. You should start roaming and gank other lanes. If you did you skill order properly, you should easily be able to flash in a output a well 600-700 dmg with your stun and shield.
When laning phase is over, and the game enters team fight phase. Always make sure you burst down the squishy targets (Support/AD carry/AP carry). If you fed yourself properly, you should easily be able to take out 70+% HP from a squishy target.
The greatest counter to an AP Sion is Banshees Veil . This item eliminates half of your damage output. Try to get someone on your team to get rid of the bubble for you.