KYS

troll: Keep Yourself Safe
salty: Kill YourSelf

*WARNING* the examples below are cringe-worthy, read at your own risk.

* unlikely scenario *
Person 1: KYS
Person 2: ?!
Person 1: keep yourself safe ;-)
Person 2: haha!

* likely scenario *
Person 1: *makes Person 2 mad*
Person 2: KYS kid!