Hi ;)
Its my first build here and at the start I want to sorry for my poor english, its not my native language, I do a lot mistakes so u can correct me in comments :)
I will shortly explain my (imo best) ap/lane build for Skarner.


I played with him about (only) 15-20 Games so soon there will be more better guides :)


Enjoy.

Centuries ago, there lived a race of creatures as ferocious as they were wise. The brackern were unusual beings blessed with the earth's primal magic, embodied in the form of crystals. Their kind knew of an arcane ritual to bind their life's essence to a crystal, communing with the magic embedded in it. With this power, the brackern thrived in the Odyn Valley, protecting both creatures and crystals alike. Despite attacks from those looking to claim the primal magic, it seemed that nothing could get past the brackern's defenses. Nothing, that is, until the devastation of a Rune War.

A vicious battle was fought near the Odyn Valley and the unleashed chaotic magic poisoned the crystals. The brackern began to grow sick and die, and no amount of defensive magic could reverse the effects. To avoid extinction, their only course was to hibernate underground until the wars stopped. The strongest, most intelligent brackern hibernated closer to the surface to awaken first and assess the world's condition for the return of their race. The recent mining operations and violent escalation in Kalamanda were enough to awaken the first of these vanguards. When Skarner burst to the surface, he lashed out in anger and confusion. Reason eventually won out over his anger when he realized that the agents of the League who found him were simply functionaries. Skarner was invited to the Institute of War to share the brackern's story. In return, the summoners told him about the history that his kind had slept through. Much had been done to curb the unchecked use of magic since the Rune Wars, but it was obvious that the world was not yet safe for his kind to reawaken. For now, however, there is a place where Skarner can use his power to change the world into one to which his kind could eventually return: the League of Legends.

''The humans have not yet learned to control their magic - what once was Kalamanda is now a crystal scar on the history of this world.'' � Skarner

Pros:

+ His E is good harass tool in early game
+ good selfheal
+ funny to play
+ spamable skills
+ epic voice :)
Cons:
-squishy
-CC'ed easily
-Not easy to master

For runes I have chosen my old runepage with some M pen and m resist ;)
works good but u can improve that in your way ;)

9x Greater Mark of Magic Penetration
9x Greater Seal of Ability Power
9x Greater Glyph of Magic Resist
3x Greater Quint of Insight


As u see nothing worth explaining :) Some magic penetration from Marks and Quints, a little AP from Seal (but i think armor penetration here would be better)
And magic resist Glyphs.

Masteries are simple too:
9/0/21 for more magic penetration ,CDR and improve Exhaust spell
I treat him like any caster, so 21 in utility is must ;)

I dont want suggest u only one way to leveling your skills

For first skill I taking Ixtal's Impact - And im trying to max it as fast as it is possible.

2 max skill depends on enemy if your enemy is agressive max your shield Seismic Bastion

And this is time to think a little more
I had some problems with election of good items, i hope u will like my way of building him.

Early:
I start with mana crystal and some healt Potion, this allow me to spam Q/E skill and stay on lane realy long. I B'ing when i reach 900-1k gold , and i spend it on (and ward if needed)
Next we will need boots - im using only if enemy team is heavy CC) or .

Mid:
We should start building - It's core item which give us most of our AP.
Next Should be
And now we can do some serious DMG.

W + autoatack + E + Autoatack + Q + autoatack sequence will be pain in the *** for every enemy ;)

Rest of the items should depends on enemy - if u need some defense build up or [
For good DMG boost u will need

Optional items:

Flash - U will need it becouse of lack of escape mechanism.
Exhaust - great for chasing or escape, i found it usefull for easly hitting enemy with Skarner ulti.
Ignite - good for finishing enemies.
Ghost - usefull for chasing and running

Skarner is very team depends champion.

You should lane with good DPS champ, then almost every of yours succesfull ultimates will end with kill.

in team fight u should be placed in the middle of fight and spam ur q+e combo, avoid being focused and be carefull for CC.

Skarner is good jungler, However if u like jungling this build isnt for You :)

Thanks for reading.
If u think something is wrong (or i did mistake) feel free to correct me in comments ;)
This is my very first build and all in all my first web publication in english so dont be mad at my english ^^

Good Luck Summoners.