I KNOW I KNOW I KNOW wtf right? The build is looks odd. First off this is my first guide, and to be honest I am not an analytical person. So you won't get a whole lot of %% and figures backing up my build. Just try it out. I have played several champs and was decent with most, but after I figured this build out I actually payed CASH for Skarner (which is the only money I have spent on this game) and got a skin. And felt good about it lol.
When I first looked at Skarner he was a freebee and everyone was playing him, AND everyone sucked @#$ with him. I thought surely Roit wouldn't have thier week old champ be completely fail. So I tried him out for 5 games using all the builds I found here on moba. And if you have tried em then you prolly feel like me about them....eh....blah he still ain't great.
Well he is great just not built like THAT
Using this build several times my friend (an avid talon player) and I have 2v3 and won, for those pesky "omg my connection sucks" teammates

Pretty easy
Glyphs more magic resist more survival
Seals More armor more survival
That and he doesn't benefit as much from anything else in either of those two categories
Marks I HAD armor penetration cause more armor pen means more damage right?
WRONG he uses a lot of spells so spell penetration more damage right?
WRONG the faster he hits the more often he gets to use spells. winner ding ding alacrity
Quints pretty much same thought process as marks

Ok everything on the Offense is a MUST
A point into improved ghost is a must
and the rest just makes him beefy

Pros-
His ult is one of the best, especially when combined with ghost and his W, DRAG 2 LAZERS!
He can mow down minions like a lawn mower
About level 6 you are constantly casting at least one of you spells which is fun pew pew
Everyone underestimates Skarner right now
Teammates will love you because of your Q's CC and your tail drag while they beat them
Cons-
with this build...ya'll will have to fill me in because I really am bias

The skill sequence is non negotiable.
putting pts into with shield (w) before E is a waste, your shield gets popped quickly which means you dont really benefit from the attack speed bonus from it for very long.
Get the more damage by leveling everything else up first and saving W for icing on the cake
Q maxed first is a must too because it is the fastest cooldown, its your CC, and its for farming tool. and it does the most damage *shrug* any more reasons needed? it makes a wicked cool circle?

Ghost and Exhaust are the only spells you should use
Ghost helps you escape with W and also is AWSOME with your ult
Exhaust will make you able to take down champs like tryn or xin if you hit them with it early so that their dps is fail, then when it is off tail drag them while spamming Q and finish them off.

flash and ghost is what I use on EVERY other champ but skarn NEEDS ghost and exhaust trust me If I don't have them then even I get waxed with this build

Try these items in this exact order for at least 3 matches that you have decent team mates. If you want to drop something then the warmogs is really the only thing that I would touch. the manamune is kinda there just because we have AND NEED the tear so you can go arch if you want but i like manamune because at that point you dont need the mana from the arch staff. Any suggestions I would be glad to discuss

Tear of Goddess - Skarner is mana hungry because when fighting he CONSTANTLY is spamming abilities. Small investment for most return and keeps you from needing Mp5 runes

Berserkers Grieves - After the tear your mana problems are solved so there are only two left Health and attack speed. Normally I say that berserkers are a waste, get attack speed with other items noob. BUT in skarners case ive tried doing it every other way. And he needs the speed early on they are cheap and make a HUGE difference when him

Giant's belt - Your attack speed is good for a few levels but you NEEDS tankyness, health is a must and this is the game changer right here, as soon as you get this item you start to love skarner. Skarner is NOT a burst champ so buying him time to out sustained damage the champs is the only way to go sooooo health is a must. If you are doing good get this before berserkers.

Stinger - ok your health is beasty now you need more attack speed and and cooldown reduction is nice too. all around a must for Skarner next

Phage - building towards frozen hammer and you hit fast enough that this pretty much does what the hammer does anyway so you can grab it instead of going all the way for the hammer

Malady - Read its description, it was made for Skarner

Frozen Mallet - already mostly built and all its stats help

Nashars tooth - Finish build from stinger, read description another made for Skarner

Warmogs/manamune - only two debatable items in the build. I get manamune because you HAVE to get tear and at the point you buy it its better than the arch staff in my opinion becuase i seemed to get more damage out of it and i dont need the extra mana from the staff. the warmogs i get because i dont need more mana, attack speed, and health makes you last longer. I would say maybe a crit item would be nice instead but i havent tried it. Most the games dont last long enough to get these last two items

If you see a team mate running your Q will slow on the second cast. use it and save a teammate
If you see a team mate running your tail WILL save them
Let you teammates that are near know that you are going to drag, that way while you drag they melt him
pop W ALWAYS before a drag, if you have ghost up pop it 2, then pop exhaust to gaurantee a kill even if they flash, you can put exhaust while you drag as well as spam Q while you drag to keep the CC active
Getting Q first helps with level 1 ganks just fyi, you can kill at least one even if they flash with your CC and exhaust combined
Hit as many minions with E as you can and then get close and hit Q, yup Q counts as a hit on all of them
with this build you can solo dragon at 8 BARELY and have 1/3 health left at 9
Dont forget to use your potions, make it a habit i had trouble with that for a long time too best way is to pop it as SOON as you take damage in the first fight
If there is a blitz on your team, coordinate with his pull and your ult and laugh at the rage and surrender at 15. Towers kills are funny when you do it to someone