The Cygnus Coin, one of the one hundred Constellation Coins in Endless Ocean: Blue World, can be found in Ciceros Strait, at co-ordinates B-5. The zoom-mode patch where the player can find this coin is found on the rock shelf above and to the west of Amphitrite's Sanctuary (the small area of ruins in western Ciceros Strait inhabited by Manta Rays). This zoom-mode spot also contains two Threadfin Butterflyfish sharing their space with the coin.
- The word 'Cygnus' means 'swan' in Latin. This is where the modern word for a baby swan, 'cygnet', comes from.
- There is a character in Greek mythology called Cycnus, who was the son of Poseidon and a sea nymph called Kalyke, and was said to have killed a thousand opponents in the Trojan War, siding with the Trojans rather than with the Greeks. After his death, he was transformed into a swan.
- This coin is found near Amphitrite's Sanctuary. Amphitrite was a sea nymph like Kalyke, giving some relation to the location of the coin and nearby landmarks.