I love Skarner, he is sorta blue reliant on his first and second clear, after that you should have a philo and a sheen so you can start to give blue away. I have never bought a frozen heart on Skarner, though I can see it being really good on him. I normally build Skarner as an off-tank so there isn't room for it in my final build.
And a good thing to know, only give blue away if you trust your AP mid. I almost never give it away to randoms unless they are someone like Swain or Anivia who really need it and they aren't losing their lane.
---------- Post added 2012-08-08 at 04:35 PM ----------
Tiger Udyr and Phoenix Udyr are two completely different champs pretty much. Tiger has great ganks and shit clears. Pheonix has awesome clears and okay ganks. I always prefer phoenix over tiger because the only way you aren't gonna have a successful gank as either Udyr build is if your laner is asleep, and since phoenix clears better you can gank and counter jungle more.
If they don't flash, I never have a problem getting a kill with Phoenix. Also for a starter jungler, having that quick clear speed is a big +.
I've heard the new champion Diana is AMAZING and very quick at jungle. She is decently tanky plus lot of burst damage. Can jump to her target and also her E let's her pull everyone in like Oriana's ball.
I also have tried the new Evelynn jungle and she is also very fast. A lot of my friends who couldn't jungle before played her and were able to pick up jungling. (:
Good luck!!
Nocturne is a good starting point, as is Nautilus and Maokai. All relatively easy to gank on as well as generally clear camps
Warwick is really easy to use and is a great jungler. Shyvana also a great pick after having more experience jungling.
Those are terrible starting points because all three of those are 6300 IP champs. Waiting for a champion to be free can take awhile, and you don't wanna try a champ for the first time and realised you dislike him and just wasted 6300 IP on them...
And Swiftkid50. Warwick is a terrible jungler. He is great to learn with as he is a good baseline jungler to compare other junglers attributes to, he has good sustain, and hes, he is easy to use, but compared to most other junglers, he really isn't very good. No ganking power pre-lvl 6, and after lvl 6 his ganks aren't that much better then most other junglers. Slow clear speed, etc. He is good to start off jungling though.
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