I want to caution anyone reading this article — “synthetic weed” is extremely, extremely dangerous, far more so than salvia.
Plain old weed is well-known. As vices go, it’s less harmful than most. It’s less habituating than tobacco or alcohol, has fewer negative effects on your body, and tends to make you relaxed and cheerful. Yes, if you use it all the time you might lose a bunch of motivation.
The original synthetic weed was just that — synthetic THC — not really different than strong pot.
But the Feds made that illegal. So people responded by replacing the THC more and more exotic compounds with very little clinical history.
Result: terrible badness. Seizures, deranged rage, self-harm.
Stick with real cannabis, or if you want to go deeper, classic psychedelics like acid or shrooms.
Salvia is… interesting. I wouldn’t recommend it myself, but the toxicity is low and it lasts for a short time — you might find it educational. Just make sure to have someone around to take care of your body while you aren’t using it. :-)