Aboriginal people believe that Ngalyod, the Rainbow Serpent, created many sacred sites in Arnhem Land, including a large billabong near the artist’s camp high up in the Stone Country between Oenpelli and Maningrida, where he is supposed to rest in the dry season. Characteristics of Ngalyod vary from group to group and also depend on the site. He can change into a female serpent, and has both, powers of creation and destruction, most strongly associated with rain, monsoon seasons and the rainbows which arc across the sky like a giant serpent. He is most active in the wet season, preferring to spend the dry season in billabongs and freshwater springs where he is responsible for the production of water plants such as waterlilies, vines, algae and the cabbage tree palms, his favourite food, which grow around the banks.

When waterfalls roar down deep gorges, it is said that Ngalyod is calling out, and large holes in stony banks of rivers and cliff faces are said to be his tracks. He is held in awe because of his swallowing of people who offend him. Often when Ngalyod swallows people during floods which he has created, he regurgitates them and they are transformed into new beings by his blood. The white ochre used by artists in the area to create the brilliant white paint on bark paintings and body decorations is said to be old faeces of the Rainbow Serpent.

Aboriginal people respect and caretake sacred sites where the Rainbow Serpent is said to reside, and forbid certain activities such as cooking to take place in case they incur the wrath of the serpent, resulting in sickness, accidents and great floods, which make it easier for him to swallow his victims. He is often depicted with two gristly bones protruding from the back of the head. This enables him to burrow underground more easily. Although Ngalyod is generally feared throughout the Stone Country, he is a friend and protector of the tiny Mimi Spirits, which sometimes curl up and steep within his coils, where they feel safe.

Maraiin ceremonies, which are secret and sacred, consist of a series of song and dance cycles which last for several days. Song men chant about the deeds of ancestral beings to the accompaniment of a clapstick man and didgeridoo player. The most important song cycles relate to the Rainbow Serpent. Water Goanna, who created waterholes by urinating throughout Western Arnhem Land before being transformed into a goanna, shares song and dance cycles with the Rainbow Serpent in the closing sequences of the maraiin . Huge wooden replicas of the two reptiles are borne aloft on the shoulders of dancers onto the dancing ground, where other dancers are imitating the slithering actions of these revered creatures and their deeds when they were alive.