What makes for a champion that is good at invading an enemy jungle? What makes for a champion that is susceptible to having his jungle invaded? What are the factors in the game that makes you confident to start invading?
In order to invade safely you must have a jungler that can:
- Clear camps fast (To allow you to get in and out quickly)
- Be able to escape (To get out if the enemy team converges on you)
- Move Quickly (To get more counter jungling done)
- Be able to One v. One (If you run into the enemy jungler)
For these reasons some of the best champions to counter jungle are Shyvana, Udyr, and Skarner because the can move quickly to get in and also escape, and be able to clear camps fast.
Note: Other junglers are good at counter jungling such as Shaco, Twitch, and Evelynn becasue of their stealth, but they are not the best junglers (except Shaco but he is a risky pick)
I usually jungle as Shyvana, who is a really fast jungler, and I think she's good at invading cause she can deal quite a bit of damage early game using her Burnout. She has a movement speed steroid if things turn sour, but there are other champions like Shaco who can evade better. The three main attributes to look at for invading early game are:
Survivability: How much health can you have while you invade?
Escape: If the enemy is beating you or calls for help, how well can you get away?
Strength: How confident are you that you can kill them before they kill you/escape?
Riven is one of the best junglers to use for invading. She's an extremely good duelist, clears camps quite quickly, and has high mobility with her 4 dashes and a stun. If you do come across the opposing jungler, she is very good in 1v1 fights.
Lee sin is also a very good invader, due to his mobility, sustain, and high damage output.
Any champion can be used to invade, as long as you know their jungle path. Thats all that there really is to it. Wards and CV's can tell you where they are, and you can always walk into the other side and take it down.
As far as the safest invades, that would be shyvanna, or gp usually. Shaco is obviously the best at invading as his boxes can easily kill you if you try and stop him, but hes not that viable late game. GP is great at safety because he has move speed buff + anti cc. So even if ryze from mid comes to stop you with the jungler, you have a chance a getting away. Shyvanna is a good choice because she can kill faster, and move fast. Lee Sin is a top invade jungler, because he wins 1v1 at the start of games. (Attack speed slow + %missing hp nuke). Udyr is another great invade because he has a stun, move speed buff, and can clear things fast.
Between all of those, the choice to use based upon who you are against. Try and pick a jungler who is faster then the other, so you lose less of your own farm time. Go for one who can both counter jungle and gank. Even if you steal half the jungles buff. If he ganks and kills twice, and you don't. You are behind.
Technically you can invade with any jungler, the best picks would be shyvana, mundo and udyr just because of their fast AOE clearing skills.
What you need is wards, the main danger when you counter jungle is getting pincered by the enemy team giving them a free kill, but if you have wards, you can keep an eye on their jungle, where their jungler is, where its safe to see what camps you can take etc.
Actually, talking as a experienced Rengar main jungler, Rengar is a pretty good counter jungler.
I usually start at blue, making sure to get level 2 with Q and E, and 3-4 Ferocity stacks. Then I go to enemy red, and I wait; if they start red without checking bush, it's even better. Just look at red's HP and make sure to Smite-steal it so you get a level advantage (which results in a higher HP amount and higher attack damage) then jump completely on the enemy jungler (Q first, E after if you only have 3 Ferocity stacks, then Ferocity Q). You do around 100-150 with the normal Q and 250-300 with Ferocity Q, so you always win a 1v1 fight, and are mostly guaranteed first blood.
I've succeeded doing this 25 out of 30 times; the other 5 times I failed because enemies flashed over walls or warded and got myself into a sticky 4v1 situation (jungler & mid laner & ADC & support vs. me :S). But mostly, it works. If the enemy jungler is Amumu its already a GG WP early game, because he has almost zero sustain/damage, so you kill him instantly!
Everyone seems to be answering 'what junglers are good at invading?' instead of 'What jungler should I invade?'.
Good junglers to invade would be junglers who will be taking a lot of damage from their jungle. This makes Mundo a prime candidate. His first clear can be scary because in order to clear he must lose life. It puts him extremely at risk for an invade (but he doesn't jungle often).
A jungler that you might want to often consider invading is Amumu. He has a pretty fast clear, but he takes significant damage since he has no early sustain without spirit stone. Also, his first clear is very important. If he loses blue buff, he becomes very difficult to jungle with early and it really sets him behind.
In general try to invade junglers who are weaker at dueling and/or take significant damage from the jungle creeps.