Happens on Pathfinder, Rise of the Runelords campaign, I'm the DM.
The group is a human barbarian, a humain druid, a human cleric and an halfling ranger. We were playing since the morning and it was about midnight when they encountered a quasit.
Long story short, the fight was way too long (about 2 hours), because they kept failing the rolls and the barbarian couldn't reach her. At some point, the cleric (10 STR and 10 DEX) proposed to launch the animal companion at the quasit from an elevated spot (about 6 meters high). Epic fails, the animal falls lamebtably on the lower ground.
Then, the barbarian, who is constantly challenging the druid's companion, asks to be launched. Nat 20 on the STR check for the cleric, 25 Acrobatics for the barbarian, nat 20 on attack check, critic confirmed. He sliced the quasit in 2 halves mid-air before getting down on both his legs near the liying animal.