It just only depends what build you would use(AD or AP),because if people are mainly magic resistance you have to play AD build,as long as you like it please VOTE!I will talk about Summoner's spell and the items quickly so enjoy the guide ^^!

Pros
Using Impalecan kill someone easily during TeamFighting
Spamming all your skills while fighting
Only die 1-3times only
Great CC Champion
Easier to jungle if you have the RIGHT RUNES
You will understand how to use Skarner properly

Cons
Very Squishy(keep dying)
Bad at using Impalein a incorrect timing
Bad Jungler
Incorrect items and bought the most expensive item first
Following the BAD BUILD

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

It is really fun when skarner starts playing team fight because you know,you drag people and start to rape them.
When you Drag people with you Ultimate ,it have to be the nearest people(obviously)and also must always stick to your team mate,or other wise your ultimate won't work well and can't kill them.
You spam your Q when people are trying to run so you could slow them down,when you're on low health you have to spam your W and E so you could survive easier,also more chance of escaping.

AP Spell Tutorial for Skarner:
Well when I use AP skarner I don't know why I always got on low health very quick so I think I should put Teleport on AP skarner build,Ignite is very useful for Skarner because once you drag the enemy you start to used Ignite even they run away you could kill them.

AD Spell Tutorial for Skarner:
There nothing much special about AD skarner's spell,if you use exhaust it can be enemy running away or using your ult when you cast exhaust on the enemy,but flash could be useful as well because you can escape easily and also you could use your ultimate once you have flash next to him

Skill Sequence:
First you should use Crystal Slash and spam it,while you're spamming it your second skill is Crystalline Exoskeleton then last one is Fracture .You only use your ultimate once you're on low health or anytime but never do it somewhere in the jungle.

EnergizeEnergize:
Basic attack lower the cool down of skarner's abilities by 1 second against champions and 0.5 seconds against on non-champions.
This passive is very useful when you have used your ultimate ,especially
in the fight.

Crystal Slash:
Skarner lashes out with his claws,dealing damage to all nearby enemies and charging himself with Crystal energy for 5 senconds.
This spell is the second best skill because when you spam your Q ,it can slow the enemy down and it's an AOE so it's very usefull for the team fight.

Crystalline Exoskeleton:
Skarner receives a shield for up to 6 seconds which blocks damage.While the shield persists his movement speed is increased and his attack speed is increased.
I think this spell is alright when you play jungle with Skarner,it will gives you movement speed and attack speed,team fight can be useful as well but it will more like a KS :P.

Fracture:
Skarner summons a blast of crystalline energy which deals magic damage to enemy struck and mark them for 6 seconds.Any further damage dealt to marked targets by skarner will allow him to consume the mark to heal himself for health.Subsequent marks consumed will heal for 50% for last.
you only used it when you're on low health but also you could spam it in the team fight,this spell is the only spell that is range on Skarner so once people is trying to run away you could use Fracture and slain an enemy.

Impale:
Skarner suppresses an enemy champion for 1.5seconds and deals magic damage to it.During this time, Skarner can move freely and will drag his helpless victim around with him.When the effects end,Skarner's target will be dealt the same amount of magic damage again.
The best spell on Skarner,but only good for team fight,once you drag the enemy you could start raping them with your team-mate.

AP Skarner's Runes:


AD Skarner's Runes:

Items you might need:



Starting items:
AP:

AD:

!!!!GET SHEEN FIRST ASAP!!!!
THE BAD STARTING BUILD
AP:

AD:
or

Farming for Skarner is very easy because Crystal Slash(Q) cost very less MP,plus once you have auto attacked you can use your Crystal Slash(Q) and destroy the minions,aura skill and it could slow down once you keep spam it while you're farming.
Using Fracture(E) can farm as well but it cost more MP,it can used it for healing as well while you're farming,but you need to cast Fracture(E) fire then you use Crystal Slash(Q) ,so also you could heal yourself during farming,in the late game you can probably kill the minions within those 2 skills.

Very sorry about my grammar so I hope you will understand what my guide is talking about,also i hope you would like it,I have give all my best efforts to do this,I would be appreciate if you will vote for my guide.


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