Mentor is a triggered ability. “Mentor” means “Whenever this creature attacks, put a +1/+1 counter on target attacking creature with power less than this creature’s power.”
May 3, 2019 · War of the Spark
Afterlife is a triggered ability. “Afterlife N” means “When this permanent is put into a graveyard from the battlefield, create N 1/1 white and black Spirit creature tokens with flying.”
January 25, 2019 · Ravnica Allegiance
Afterlife is a triggered ability. "Afterlife N" means "When this permanent is put into a graveyard from the battlefield, create N 1/1 white and black Spirit creature tokens with flying."