Many 80s cartoons were created in a sort of ratings gray area because the rules of what kids should and shoudn't see in a cartoon were being rewritten and redefined.
And while topics like death, drugs and the Satanic Panic were considered too dark for a G audience in the 90s they were just fine for kids watching The Smurfs and the Care Bears in the 80s.
In the Care Bears Movie II a girl named Christy sells her soul to Dark Heart the shape-shifting demon so she can be better at sports, which seems pretty damn dark for a Care Bears storyline.
But then the scene takes an even darker turn when Dark Heart leaves Christy for dead, the Care Bears unable to revive her without help from the audience, who were probably in tears since they thought the girl was dead.
The Smurfs had a similarly Satanic-themed episode that deals with the Christmas Stranger, a sinister guy who buys two orphan kids from Gargamel to use in an evil ritual.
The episode also had a similar "don't trust strangers" theme and the Smurfs use the power of love and hope (and singing) to defeat the Stranger.