I love playing skarner and found it very consistant after a good time playing it.
Why did i choose skarner to main?

1-I have a duo, this makes skarner amazingly strong, because 2 secs supression with a person that knows your intention is game-changing.
2-Skarner is very independent of the team to fight enemies and making objectives, everything is better if the team got your back, but only with your crystals you're a danger to the enemy team.
3-You clear jungle really fast, probably only behind Shyvanna in speed.
4-It's pure gold, guaranteed fun.
5-Skarner is very strong at 1v1 and incredibly strong at 1v2 in your crystal zone.

=-=-=-=-=-=-=-=-=-=-= Early Clear =-=-=-=-=-=-=-=-=-=-=
ALMOST 90% OF THE TIME START ON RAPTORS, if your mid laner has any AoE damage skill start here. Use Q as much as you can, With talisman your life will be always high, after raptors go to Red camp, kill it with your E (watch out to use E trough the wall and hit red before it atacks to cancel the first atack and stun it) After red go to the Scuttler to fill your health. then gank mid or bot, probably bot still warded, so mid is easier. If decided to go bot try to counter gank, and if you gank mid go to the opposite side that you've started and farm your entire jungle, then gank mid again if possible or go base to capitalize your gold. Pre 6 the enemy normally don't care much about you for thinking that you do nothing without your ultimate, but With three levels on Q and 1 in W and E, you gank gank pretty hard, If you are able to land E in 2 or more targets hit the closer then if needed flash to secure the second stun. Dragon is really wasy with skarner after lvl 7-8 and boots with stalker's+warrior.

1- Talisman gives 25 health over 5 seconds per creep beeing hit, so in the wolves and raptors you can easilly fill your entire life up with Qs, take three potions because it gives more sustain, but after some experience with the champ and kiting the JG creeps, refillable potion is all the way more useful and cheaper so change as soon as you feel confortable.

2-Boots for clearing speed and ganks, if not able to buy stalker's, buy machette and long sword to compensate, control ward is one of the best itens in the game if well placed, so watch out for guides and tips to put them better.

3-You're an natural warrior, so this is the enchantment for you, you are already tanky at this point because of W and CCs that keeps you healthy what means you don't need cinder's,
Mercs or Tabi are both really good for skarner because you rely on your skills to damage and play and don't need berserker's.

4-Here we are, this is the point where no one can solo deal with you, If you are ahead buy trinity for all these awesome stats and burst with Sheen+E proc, but if your team needs a tank or you're getting caught out of position or have been hard counter jungled, buy iceborn gauntlets, amazing tank stats with a little extra CC that will help you to stay alive. Sterak's Gauge is simply an item made for skarner, it gives you AD based on your base AD, and skarner has the HIGHEST base AD in the entire game, and the passive that gives shield is perfect to enter the enemy team and pick anyone with your ult and leave alive (don't need to talk about the Hp that raises your shield power).

5-DMP- Mobillity in skarner works just great, like i said, extra CC is always viable, and the speed is pretty good to chase or catch assassins, that are in the meta right now.
Thorns- Against Heavy AD/Auto-Atackers teams and if they have and fed master or adc IE.
Abyssal Mask- This is a good measure to deal with APCs and has an great utility with passive, just like ''expose weakness'' every enemy champ in the range suffer +10% magic damage, so if you ult someone, it will take +13% magic damage, that's insane.
Gargoyle- If you're looking to get really tanky and jump in the middle of the enemy team to disrupt them this is your choice, awesome active that makes your shield incredibly strong, allyied with Sterak's your almost unkillable.
LotISolari- recommend this with gargoyle For the 1,2k Group shield.

6- Randuin's is like Thorns, against heavy ad and crit.
Warmog's- to deal with a lot of mixed damage health is just perfect.
Visage- Works fine with the supports meta that heal all the time, soo you can get these as an AP counter.
Frozen mallet- this is a joker, skarner already has the ability of chasing and orb walking anyone, but ad+HP+Slow on AAs can fit in some comps.
Titanic Hydra- Simple, splitpushing 4 life, this is a weapon to gain attention, you can delete one wave with AA+Q+Titanic, so the enemies will have an enormous problem if don't stop you.

Passive CRYSTAL SPIRES- This is the most important feature for you to master, this is why he's soo good at jungle, first little trick, before even minions spawn, you can go to the river an catch one crystal, this grants you 15 gold, and 14 if you're with your duo, this can be nothing for the wrong eyes, but 15/14 gold is like killing 1,3 raptor more without taking any damage. When you're inside your passive, it's hard to face you, because you get move speed to chase or run, Atack Speed that helps to trade and with more AAs you have your Q more frequently and you gain 2% of mana every sec, against creeps it's unfair and against enemy jungler it still unfair.

Q CRYSTAL SLASH- This skill deals A fast phisycal damage and if chains it deals magical damage too, what turns it in a perfect weapon for jungle, since the mobs have different resistances. You AAs reduce the CD of the skill in 0,25 sec, within the passive range you got a good clearing tool, and AAs reduce 1Sec CD if hits a champ. There is no mistery in this skill, is your main damage source and deal very well with any type of enemy.

W CRYSTALLINE EXOSKELETON - Grants a shield that is based on your life amount, its good to sustain in jungle and to move from camp to camp,With the crystal activated you wont loose mana on using just for Movement speed.

E FRACTURE- This skill is insane, you shot a crystal that slows enemy and it pass trough everything, hitting multiple targets, the targets caught by the skill receive a mark for 4 secs, if skarner hits the thing that is marked, the enemy gets stunned, in jg it's pure gold because you can stun al the three wolves to deal a lot of damage, all raptors to kill them with 1-2 hits, scuttler to decrease its defenses and etc... but there is the best part, when you stun and enemy or supress it with your ULT, you gain the passive Buff, for the duration of the CC, and your E get its CD reduced for the same duration, so E+AA+R makes you get an asteroyd of move speed, Atack speed and mana for at minimun 3 secs, even if you're away from your crystal zone.

R IMPALE- The skill does a good quantity of physical and magic damage to a target and links the target to skarner, that can move freely(capable of using W to increase speed) and dragging the target with him, for 1,75 sec the target will be supressed, and then the target will take the first mixed damage again. There's one of the most annoying skills to play against in the game, because skarner can run very fast with you (he gains move speed from passive and can activate W for more) and at the end he can step back and turn your positions, letting you closer to his team and between them and skarner. It's very good to train this move in training mode to improve your precision.

Skarner is not in the meta but still very viable because it can be as tanky as maokai and as damage dealer as Jarvan 4, it's flexible, and IMO it's very funny and you can enjoy making some great plays for highlights. Any question or thing do add, email me kaio.fegon@gmail.com