Karma, Gromp trick
I'm not sure how well known this is, but one of my favorite tricks with Karma when I'm low on health is to stand on the opposite side of the wall as Gromp, place a ward next to him, and use a Mantra empowered W (Renewal) on Gromp and get a huge chunk of my health back essentially for free because he will reset before he can deal damage.
I'm sure there are some other good spots where this can be done fairly well, and you can always just kite most camps and take little to no damage to accomplish the same thing.
Keep this in mind next time you are playing Karma and save yourself a trip back to heal up.