I've always been a fan of Sej and since she fell so far out of the meta I haven't played her much. After Oink's AP Mid Sej I was inspired to try something similar in the jungle (as a jungle main). Surprise, it works amazing :D. Here's my guide with the tips and tricks below to tweak the AP Sej for the jungle.

W: Always remember that W resets your auto attack. ALWAYS use it directly after auto attacking so that you can get 2 quick hits in while jungling.

Q: Use this to start a camp. Make sure to hit every minion in the camp. Be aware that using this puts your mobility on cd for a while, so if you are concerned about a counter jungle or that you'll need a quick get away, you may not want to use this.

E: Pop as soon as every jungle minion has been hit with Q or W.

From Blue Side:

1) Start red side so that you get help from your ADC and Support.
2) wraiths
3) blue buff
4) wolves
5) wraiths
6) golems
7) back for spirit stone and make sure you have 1 pot.

From Purple Side:

1) Start blue side so that you get help from your ADC and Support.
2) wolves
3) red buff
4) wraiths
5) wolves
6) wraith
7) back for spirit stone and make sure you have 1 pot.

Early Game: After your first back, I normally focus on wraiths and wolves since you are an aoe jungler, and help the team as necessary. Clear golems or wraiths on occasion, especially with smite up. You are not great as a ganker unless your opponent is really out of position since you need to land something before you can proc your E. I complete Spirit of the Spectral Wraith before starting boots to get those stacks going as early as possible.

Level 6: At level 6 you will need your ally to do a decent amount of damage to secure a kill, since you haven't yet locked in your haunting guise and sorcerer's shoes. Regardless, landing a full combo can really turn a lane around since it will easily do half health on most champions. I regularly gank when my ult is off cd. Lane ganks are especially powerful bot lane as your ult range is very long and your support generally has follow up crowd control.

Mid Game (haunting guise and sorcerer's shoes): At this point, you do lots of damage. Not enough to 1 shot squishies, but often enough to do 90%. Remember you need to use your Q for damage, not just mobility since it does an insane amount. The risk is always that it costs you your mobility, but I often find that you can walk away after R/Q/E since they are so slow. If worst comes to worst you can always flash out afterwards and watch your team clean up.

Late Game (void staff, DFG): You can 1 shot squishies. If you ult and E a squishy, they will lose over 2/3 health and tanks around 1/2. This is a huge amount of damage, considering you can only dfg and Q 1 enemy for instant death.

Remember, you are a high burst caster! Once you blow your cd's, just back up and wait for them to come back up. Once they do, head back in for another round of damage. Often a well placed combo will mean that your team has cleaned up before you even get a shot at a second volley.

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