Loch Ness Monster

The Loch Ness Monster (colloquially called Nessie) is a cryptid, a creature whose existence has been suggested but has not been discovered or documented by the scientific community. It is reputedly a large unknown animal that inhabits Loch Ness in the Scottish Highlands. It is similar to other supposed lake monsters in Scotland and elsewhere, though its description varies from one account to the next. Popular interest and belief in the animal's existence has varied since it was first brought to the world's attention in 1933. Evidence of its existence is anecdotal, with minimal and much-disputed photographic material and sonar readings.

Mainstream Smurfs Media
In the cartoon show episode "Hefty Sees A Serpent", Hefty as well as the local village fisherman Angus McGarg claim to have seen what is called "the Loch monster" and "the sea serpent", but were doubted by their respective people. However, when Angus McGarg tried to use the Smurfs as bait to catch the creature, Hefty helped turn the tables and had the sea serpent rescue his fellow Smurfs while dashing Angus' boat upon the rocks, leaving Angus to be the laughingstock of his community while the Smurfs became believers of Hefty's claim.

Empath: The Luckiest Smurf stories
In the EMPATH: The Luckiest Smurf story series, the creature is referred to as "the Loch monster" by Duncan McSmurf, who says that this has been the legend of the McSmurf clan for generations, though during the time-traveling adventures of The Lost Year, Hefty was the first to actually see the creature for himself.