>>41050502 (OP)
all creatures (giants, nagas, reptiles, werewolves, satyrs, fairies, kelpies) have illusion magic in myths and stories. Hindus and Buddhists believe that nagas are the main illusionists and periodically come out to people, it is difficult to see their real nature
Kelpies are real by the way
In 1846 Captain Christmas of the Danish Navy reported sighting "an enormous, long-necked beast pursuing a school of dolphins" somewhere between Iceland and the Faroe Islands. He described the creature as having a horse-like head and a neck as thick as a man's waist "moving gracefully like a swan's".
On 6 August 1848 an officer of the Royal Navy corvette HMS Daedalus noticed an unusual looking animal swimming towards the ship. It was said to look similar to a sea serpent with a 1.2-metre-long (4 ft) neck. Its head was about 38 or 41 cm (15 or 16 in) long. It was reported to have no visible fins/flippers or tail, and it had what appeared to be a horsy mane on its neck with seaweed washed over its back.
In late 1883, two horse-headed beasts, one of them smaller than the other (suggesting or implying a juvenile), were reported off the southern coast of Panama. The crew of the American whaler Hope On reported seeing a 6-metre-long (20 ft) creature submerge. It was brownish coloured with black speckles and four legs/flippers with a tail "that seemed to be divided into two parts" (implying the whale-like tail appearance) and all four limbs and tail were exposed when it reached the surface. A second creature that looked just like it only much smaller tagged along behind it. In the same year, a sighting of a similar looking creature occurred in the Bristol Channel. This creature was reported as leaving behind a greasy slug/snail-like trail.