More coming soon.
Right now I'm working on explaining the Situational Items.
This is my first guide, I appreciate your feedback!

I don't think Jack Of All Trades is that good for Karma, you can get 5 different stats rather easy (World Atlas already gives Health reg, Mana reg and Health), but without building weird items or getting your Wardstone early (which I wouldn't recommend since the stats are quite underwhealming) there is no way to get to 10 different stats consitantly.

If you want to play Jack Of All Trades you'll need World Atlas (Health reg, Mana reg, Health), Malignance (AP, Ability Haste, Mana), Magicpen-Boots or CDR-Boots (Movementspeed, Magicpen if you go for Pen-Boots)
-> we are at 7 or 8 different stats right now, we can get Shieldpower from Shurelya's, Ardent Censer or Redemption which only brings us to 8 or 9
So you can only get to 10 stats by building Wardstone, but at the time you get this the game is usually over.

I really like Dark Seal!
Buy Dark Seal, if you get an early lead, Dark Seal has an amazing gold efficiency and it's cheap, which is insane for supports.
Try to stay alive, so you don't lose your stacks, positioning is king.
Would not recommend Dark Seal if you're facing a lot of Assasins with good backline access.
You can upgrade this to Soulstealer, if you have about 7-8 glory stacks and you're confident you won't die.

Coming Soon

Build Mikael's Blessing when your Carry is threatened by hard cc like Ashe r or Malzahar r, Leona...
(Mikael's Blessing can be used against supression, unlike Cleanse)
Another upside is that Mikael's Blessing gives 12% Shield and Healing instead of the usual 10%

Coming Soon

Coming Soon

In my opinion this is the best 2nd/3rd Item, the build path of 2x Forbidden Idol is really good. You can default to Dawncore to finish of your build when you don't need other items for utility.

Passive Innate:
Mantra's Mantra's Cooldown current cooldown is reduced by 4 seconds for each enemy champion hit by Karma's damaging abilities.

Q - Inner Flame:
Karma fires a bolt in the target direction that explodes on the first enemy hit, dealing magic damage to nearby enemies and Slow slowing them by 40% for 1.5 second

W - Inspire:
Karma deals magic damage to the target enemy Champion champion or Monster monster and forms a Focused Resolve tether between her and them for 2 seconds, during which they are True Sight revealed.

If the tether is not broken by the end of its duration, the target is dealt the same magic damage again and is Root rooted for a duration, during which they are True Sight revealed.

E - Focused Resolve:
Karma grants a Hybrid resistances shield to herself or the target allied champion for 2.5 seconds as well as Movement speed 40% bonus movement speed for 2 seconds.

R - Mantra:
Karma empowers her next basic ability within 8 seconds for an additional effect.
Karma begins the game with one rank in Mantra. Her empowered abilities scale based on Mantra's rank.