Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
Why Seju AP?
Lets see the damages with 600 AP lvl 18:
Q : 260 + 240 = 500
W : 6 + 18 = 24% of the enemies max health and 160 + 360 = 520 damages in 5 seconds
E : 180 + 300 = 480
R : 350 + 480 = 830
A total of instant 1810 damages and 24% of enemies max health, all in AOE.
Then 520 damages in 5 seconds
This is just huge. And you also have luden, lichbane, thunderlord, smite and up to 9.5% bonus damage from masteries. Enough to destroy a whole team on your own.
Basically, tou just want to do all your spells on the maximum of players.
You need to be carefull, because if a tank controls you, you won't be able to catch carries, that will just eat you.
Use your mobility to engage hard on the adc or mid, then fly, you fool!
The jungle is quite easy, you wont have any problem with monsters (W in % health and bonus armor with passive).
You can gak as you wave enough control with Q and E, but care, you aren't a tank.
Ult. That's all. Go on the lane, ult, destroy the enemy with your mate and go farm.
Try to hide in the bush and jump on a little carry who wanted to farm.
Remember, you can destroy a whole team on your own. This champion is perfect in teamfights, you just need a tank to engage. The best might be malph.
Your big weakness is your turrets push. Hopefully, the lichbane is here to help.