Greetings everyone and welcome to my personal Skarner build! I'll start off with a disclaimer;

I have no credentials and am a simple pre-30 player who isn't particularly good at the game yet. This is NOT a build you should follow to particularly do well with, but more of a way for me to jot down my experimentations to see what comes out.

That said, this is a build for Skarner that I've adapted to my personal preferences to see if I could make him work. I've been doing some simple experimenting with the build, and I personally prefer it over what some of the top guides recommend. Do note again that I'm far from a pro player - I prefer avoiding some items (like Guinsoo's Rageblade, for example) due to the simple fact that I'm not good enough to gain full benefit from them.

For those completely new to Skarner, here's a rundown of his abilities and a simple write-up of his playstyle.


Energize Energize
What this passive basically means, is that Skarner needs to be attacking to be able to use his abilities often. It also makes attack speed items interesting for him by causing his abilities to get ultra-short CD's.


Crystal Slash
As Skarner's main ability, this is the one you're going to be spamming a whole lot. You need to cast it twice to get your slows off, so be prepared to bash your hotkey for this skill while chasing down enemy heroes.


Crystalline Exoskeleton
Though not exactly an ability you want to spam, the move and attack speed bonus this ability gives you are the reasons why you'll want to keep this up as much as possible, especially during teamfights.


Fracture
Even though the heal from this ability tends to be pretty paltry, this ability allows you to A) throw something at a hero that is outrunning you (even if it doesn't do a lot of damage, it might be enough) and B) gain some survivability and lane longer through it.


Impale
Impale is the main reason people love Skarner. It's a combination of CC and repositioning of your enemies, what more do you want?


Basic playstyle
Skarner's basic playstyle is relatively simple. Like with most melee heroes, you're generally trying to prevent yourself from getting harassed while still getting last hits off. In the laning phase, you'll mostly be using Fracture to debuff enemy mobs, followed by running in, hitting Crystal Slash (twice, if your opponents let you) and then backing out again, taking a last hit or two if possible. Impale kind of speaks for itself - if an enemy is too aggressive, ( Flash to him), toss this on him and drag him back to your turret for a free kill. Lateron in the game, you'll use this to A) drag assassin-style characters (like Master Yi) away from your mages and B) drag enemies who aren't careful enough into your team as an initiate.

Things you need to realize to play Skarner

• You cannot cast Flash while using Impale. You can however, pop Ghost to drag enemies further back.
  
• Even though you cannot auto-attack the target of your Impale, you can still hit him with Shattered Earth and Ixtal's Impact, and you can pop Seismic Bastion for even more mileage out of your CC.
  
• Shattered Earth consumes the debuff placed by Ixtal's Impact. You can mark a group of mobs, run in, use Crystal Slash once to get all the heals, and then back out again.
  
• When you've issued an attack command on an enemy hero, none of your abilities will cancel this. Allow me to explain; especially if you come from other RTS/DOTA-style games, you might recognize the situation where you're chasing down a unit and use an ability - after using the ability, your unit will stop moving and stand there, losing you valuable chasing time. In LoL, this does not happen - regardless of the ability you cast, Skarner will keep moving to try and kill your target. In a nutshell, this means that you can spam Shattered Earth to slow while chasing down an enemy (something that will be happening a lot).
  
• Impale also CC's. In some situations, you'll want to pop your ultimate just to prevent an enemy from attacking, even though repositioning him doesn't really help you.
  
• Impale can drag players through walls.

As a little note on runes; I am currently still exploring the game myself - I'm using my IP on heroes and experimenting with that I like and haven't bought any runes yet. Because of this I have no idea what works well for him - I just gave him a couple of basic ones that seem like good choices. Expect an update in this section should I still like Skarner once I get 30 and buy myself some runes.

For masteries, there's a similar story as with runes - I'm still experimenting with a lot of stuff, so I'm simply using my basic "grab everything useful in the utility tree" build for Skarner, barring a few changes that make sense for him (I usually grab Spatial Accuracy, but since I go Flash/Ghost with Skarner, Haste is obviously the better choice). The reason I skip Utility Mastery is because I don't currently play Skarner as a jungler.

As for items, I've put some more thought into that. Let me take a moment to thank "RaskolnikovsAxe" for his "Hybrid Lane Skarner--Crystal Meth in a Can!" build, as that's what inspired me to think through Skarner and experiment with my own item build. As you can see, I pretty much copied the start of his item build for my guide.

Skarner has some problems that prevent him from being effective, and I've attempted to wrap my item build around that; the items I get are there to get rid of his weaknesses, after which he can start pumping the damage and CC.

Early game
I start off with a Sapphire Crystal, into a Tear of the Goddess; this really is purely to alleviate Skarner's mana problems as fast as possible. With Skarner's passive and his already low-CD abilities, getting the Tear early should max it out relatively quickly. Mercury's Treads are up second, simply because the movement speed is required (and a little bit of survivability seems a decent choice for him). I then add Sheen for a quick boost of even more mana and damage, and finish up my Manamune. This sets you up for a midgame where mana is no longer a problem and the Trinity Force is less far away due to Sheen. I currently play without potions at the start of the game as I find I have little trouble getting last hits and staying in there, but at a higher level they may be required.

Midgame
Once early game is over, getting a Trinity Force seems to really help Skarner out - I've heard a lot of complains about how the hero is underpowered because of his low stats, and the Trinity Force seems to offset that a bit. With these items all set, it's time to start looking into just a little bit of survivability for Skarner. Out of all items I considered, nothing seems as effective as a Guardian Angel for the scorpion. Zhonya's Hourglass might be an option, but Skarner's main problem in team fights (that will start occuring from this point) is that he's too vulnerable to be effective - running in gets you killed. Guardian Angel makes you a less attractive target and gives you a second chance. Force of Nature or Warmog's Armor seem like they could be options here though, if you're facing a mage-heavy or tankish-heavy composition.

Endgame
By the time you'll get your Guardian Angel, endgame should be starting and teamfights are becoming more and more important. With base stats and survivability set, aiming for more damage should be your best bet to stay effective. Wit's End is up first because it is easy to get and has awesome synergy with Skarner; with your passive allowing you to use your spells more often, getting more attack speed increases your overal efficiency. Aside from that, the item's passive debuff should apply and max out more easily. As your very last item, Zeke's Harbinger seems an awesome choice - even more attack speed synergizes nicely with your passive and the Wit's End you just got, and more survivability is always welcome.

Ghost is the one summoner spell I'd call a must for Skarner, and I'd daresay this probably holds up for ranked play as well. The main reason for this summoner spell is because popping Seismic Bastion alongside Ghost gives you extreme mileage out of Impale.

Flash is the spell I generally go with as my second choice, as even though it's not usable while Impale is active, it still allows you to escape more easily and catch runaways.

Other spells that I'd consider taking over Flash are
Cleanse (allows you to clear the CC that will be thrown on you when you use Impale),
Teleport, and possibly
Ignite, if you like playing aggressively and are sure you can get your stuff off (Skarner isn't the most effective Ganker, I've found).

All other summoner spells are those that I'd advise against. They either don't really fit your role or only serve a small purpose.

The way I currently view and play Skarner like is as a laner. His role is basically a hybrid assassin/beefymeleeDPSlikeMordekaiser/chaser, and playing him that way seems to work for me so far. As long as you get your mana up quickly, then get survivability and then focus on more damage, you should be able to at the very least be extremely annoying for enemies to deal with, even if Skarner is regarded underpowered.

I'm probably going to try and play this build a couple more times and might make updates as I go; feel free to add comments and tips with good reasoning as to why stuff does or doesn't work on him - we'll see if I end up with the same idea as the top rated builds eventually.