Which is better. I always though AD was best.
But other people tell me otherwise.

Explain!

Scion was my main for a long time, but I played him as tank.

That being said, I think AP is the best. For a couple reasons. There are many more AP + health items...ok 2, but RoA stacks nicely, Also the AP ratio for scions abilties are 1:1 which is op.

AD is awesome, but usually you get focus'd, if you can have a great early game and get some AD and then be workin towards frozen mallet its baller. Also AD Scion is probably the better late game build, because you dont need attack speed if you have level 3 ultimate.

Spread the love and try them both!
Sheen
Aegis
Trinity
Atmas

FTW

AD is much better.

You can't 1shot them with your shield, so its not that efficient. It is however better early game.

But inf edge+Atma's we'll say. (atma's is crazy, by the time you get it you will have 2k life just from E which means atmas will give 40+ damage 45 armor and 18 crit chance

I crit for 800 3 times in a row with inf edge. Not really hard to do at all.

800x3 2400 life back instantly just from your ulti.
(1200 for your allies)
400 life for your allies every time you hit something
imagine soraka's ulti being on a 1.5 second cooldown.
now you can 1 shot minions and farm E up, it will act as a bloodthister since your life goes up which in turn raises your AD from Atma's

I've saved so many allies just by turning my ulti on and hitting a few minions and healing them back to full life in just a few seconds, or stunning and attacking the target attacking them, and my ally lives from my lifesteal.

AP is better early game, good harasment, but he has 300 mana and each of his moves cost around 100 mana. (mana regen will fix your mana problems though)
If ap sion gets fed he is CRAZY, if he doesn't, he isn't worth much at all.

AD is a better team player, he can heal his allies, and late game when he turns his ulti on he is EXTREMELY hard to kill.

Late-game AP Sion is one of the hardest hitting, versatile, sturdy mages in the game. My buddy mains an AP Sion at the top end of the mid-ELO bracket, and he generally doesn't even need to be fed to get rolling.

AD all the way, especially on treeline. AP sion is cute but AD sion destroys whole teams.

AP sion lets you gank the hell out of your enemies and either break their will into submissive surrender or snowball your way into unkillable godmode.

AD sion lets your attacks slaughter everything in your path while bathing yourself in the blood of direct damage to hp lifesteal.

AKA
AP is good for crazy burst damage earlygame small battles
AD is good for insane late game unstoppable lifesteal tank.