Not Updated For Current Season
Mostly for my own reference, but by the off chance someone will look at this build:
Holy Fervor: Awesome.
Reckoning: Use first to slow, last to kill.
Divine Blessing: Decent heals, great speed for escapes, chases, and more importantly allied escapes.
Righteous Fury: Main skill in the cycle. Moderate range means this is also a good ability to push towers. At higher levels this will be a good farming tool, considering it's all Kayle has to farm with quickly.
Intervention: Two seconds is a lot longer in a team fight. Allies first.
The progression is flexible, but as a rule the priority is Intervention, Reckoning, RF, DB. If your lane partner needs more heals go that way instead.
Clarity: Doran's ring only does so much.
Teleport: I take this for pretty much every champion. Save your towers, destroy enemy towers, I'd say this is the best spell of them all if the cooldown wasn't so damn long.
Exhaust: Slow them down even more. Best left for others though.
Ghost/Flash: Always viable, but you already have a good speed buff. So, instead take:
Cleanse: A clean getaway combined with DB.
Ignite: Never really liked this spell, but is always good for DPS.
Revive/Rally: Insert obligatory derisive comment
All primary, all the time. Magic pen is good for marks too. Clarity seems redundant but Kayle has some serious mana issues early game... Well, I guess it isn't the best choice. Dodge is always a good seal. Warding because we already have 40 CDR. AP is a good alternative. Quintessences of Fortitude because I don't want to buy any other quints.
Armor penetration and CDR are very important.
Doran's Ring for MP regen, then onto shoes. Take either Merc or Sorcerers depending on the teams. Guinsoo's is essential and Nashor's is very good. Those are pretty much the core items. Hextech is a good hybrid item, very much so with Kayle. Don't forget the active, for even more slow. Sheen has a great passive for Kayle. These are some expensive items, I usually don't get past Hextech. Lichbane is iffy, but if you get that far into the build Bane will give you some serious power... Theoretically.
Kayle can deal some good damage but she's always best when supporting others. DB and Intervention can get your allies out of serious trouble and turn team battles around. he items I choose are there to capitalize on Kayle's awesome passive. If your team isn't doing so good, you might consider going a more support oriented item build. Innervating Locket is a good option, as is Starks Fervor to buff nearby champions.
When your attack speed gets into the assault range buildings will go down fairly quickly. This combines with Kayle's inherent mobility could be devastating. It can go something like this: Teleport to an unattended minion wave thats nearing an enemy turret, assault, when you've raised the alarm assault a little more and when your sure they're all about to pounce, speed yourself and get out. Use Intervention if they got you pinned. This is when Cleanse comes in handy.
That's all I have at the moment. I'm always open to suggestion. Please comment.