[*] Over View
- Pros / Cons
[*] Old Summary

COMING SOON

[*] Jungle
[*] Lane
[*] Use in team fights
[*] Build Explanation
- Runes
- Spells
- Masteries
- Items
[*] Build and alternate items
[*] Music to play to

Skarner is probably one of the purest definitions of tanky DPS you'll find. Tanky? Check. DPS? Check. The only issue is that his damage is low compared to how close he has to get to a target. The solution? Build damage. If that doesn't work? Build more damage. And maybe some survivability.

Pros-
Incredible survivability if played well
Consistent AoE damage
Great chaser
His ult is a great peel or initiator
High mobility
Steady damage

Cons-
Very low mana, and will stay that way throughout the game
No gap closer (though he shouldn't have one; he's a tanky DPS, not a tanky assassin)
Slow jungle
Easily gankable in the jungle (at least by Gonkplonk)
His speed boost and AS boost are easily removed
Generally weak early game
When entering a team fight, you're going to have to commit unless you have flash up
Ult is weak compared to other ults or similar abilities

This was the original snippet I posted in LoL General Discussion. You can use it as a quick summary if you don't wish to read the full guide:

Yeah, I know he sucks balls, but it;s my goal to be the VERY BEST. SO here's my unwanted guide to Skarner.
At any rate;
Jungling: While no longer a incredibly slow jungler, his jungle still sucks. Stonewall's jungle guide is here: http://www.youtube.com/watch?v=egO21s0tQ8Q
Stonewall's rune build functions quite well, though I subbed Magic Pen Marks, MR Glyphs because I'm cheap like that. Attack Speed runes are some of the best you can get for Skarner since they function both as offensive rune and as CDR due to his passive.

Skarner's lane is pretty okay, but you are not mega ranged. I've had many close range fights where just standing a duking it out resulted in me just barely getting 2 kills. I've got E on smartcast to get it off as quick as possible.

Item wise, rush dat Gunblade, stat! Early game this provides most of the survivability you need, and remember, Gunblade's active is the difference between you catching an enemy and that enemy getting away. A slightly more expensive alternate if you're not using Gunblade's active is buying both WoTA and Stark's. While not as cost effective, the aura's mean that even if doing bad, you're not a complete waste of space. (This was pointed out by Ostentatiousman, kudos to him).
Now, I've seen some people trash on Skarner's AP build, but understand that the more AP you build, the more survivability you have. Lich bane is semi-core, but you might not want to complete it until later in the game when you've built up 360 AP (doubles your shield duration).

During team fights, you have multiple jobs:
1. Gaurd dat carry! An assassin hasslin' your Caitlyn? Yank that guy off and slow him to death!
2. Activate your shield to soak up initial damage, then stay on the outskirts of the fight, damaging enemies with Q and E until you get your shield back up, then wade all the way in to the fight.
3. Mash W and go get that enemy carry! This only really works if you're fed, want to use flash, or the enemy tank is brain-dead.

Music to play Skarner to (I'm going for that more classic video game sound here) (credits go to the artists of these songs):
http://www.youtube.com/watch?v=mkCCO5dd3kQ
http://www.youtube.com/watch?v=3dKRKDn9ZJk
http://www.youtube.com/watch?v=xdEBx2uv8hc