A brief, preemptive guide on how to first clear as a mage Jungler.
How can I tell if this champion can Jungle? Go into Custom games, and try it with a few different rune pages. Getting the Right runes is probably the most important part, and they can be a bit finnicky sometimes. Seriously, I was having trouble clearing with Karthus, but when I ditched AP and tried flat CDR, it started going so much better. The important things you need to try are: Different amounts of FLAT AP and FLAT CDR Quints and Glyphs, usually all armor Seals, and experiment with 1 or 2 armor glyphs, And experiment with Attack speed, AD, and Occasionally magic Pen Marks.
What Jungle item should I start with?
Obviously Favors DoTs and AoEs, espeically AoE with CDs less then 5 seconds. One of the big marks you want to hit with CDR glyphs/quints is getting your bread and butter damage spells fast enough to keep Talisman's DoT and regen up permanently. In general, try to come up with everything you can do to keep Talisman passive up as long as possible. IE: if you're playing Ahri stand right up next to the Blue before casting your Q, then use the MS on cast to kite back, dragging the time out before Q rebound hits the monster.
Also, every time you walk past the wolf camp, make sure you throw a skillshot backwards into it, to proc talisman while you walk to wraiths
Some other champions will do better with Machete and AS/AD runes, if they can clear with just Blue. 10% lifesteal(with Masteries) is nothing to sneeze at. (Try Nasus Jungle)
A lot of mages have a weak early, and are kind of vulnerable to invades. Fortunately, the Jungle is full of walls and with some good vision control you can bully a lot of people out of your jungle before they reach you.
Good for heavy gankers like Morg, but Trackers is still a safer and effective option.
What masteries should I take?
Avoid Deathfire, unfortunately. The 7% penetration mastery that leads into is too useless in the jungle. With all the -MR riot's given camps, the flat pen leading to storm raiders/Thunderlords is better for clearing.
Test 12/18/0 first, then try 0/18/12. unless you're trying someone with healing, then start with it.
Some more specific tips (will add more if I get any requests)
A lot of pokey type champions will do better by kiting and/or CCing the big monster, and generally do much better with CDR.
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Swain is very... Interesting... His Torment increases almost all damage recieved, including damage from items
and his Auto attacks. Smite needs to be tested, to see if Torment increases it. He doesn't really have the AoE Pre-6, but he can do pretty well with an AD/AS page, starting with Machete. After 6, it only goes up from there.
Have fun Warping this new Meta. Godspeed, you beautiful bastards! I'll be practicing Soraka Jungle if any of you need me o7