Naruni Island is devoted solely to the Narunis, a species of adorable dinosaur-like animals found only in the Lost Ark universe. The only actual objective is to get the Island Soul, and there are a total of five Mokoko Seeds to find.
Because there is no Una's Task connected to Naruni Island, there is no incentive to return here once the Island Soul has been obtained and all the Mokoko Seeds have been gathered. You can always come back if you want to relax with some Narunis.
Where exactly is Naruni Island located?
Just beyond the central Wall of Procyon, in the Sea of Procyon, you'll find Naruni Island. From the harbor of South Vern, it is not far at all (Bellion Ruins) Lost Ark items.
Island Soul for Naruni Island is unlocked by completing a single mission, but don't be fooled by its seeming ease. In spite of the fact that this is a welcome change from obtaining tokens based on random chance, the process still takes some time.
Your goal on the mission (Naruni Go!) is to interact with the island's Narunis a total of 101 times; you can pick it up from the Environmental Researcher near the island's entrance (a clear reference to 101 Dalmatians).
Although it appears simple, these critters are constantly on the run. It's important to time your interactions with them so they don't run away from you while you're still talking to them to earn quest credit.
A Single Mokoko Seed
It's quite difficult to spot the initial Mokoko Seed because it's buried deep underground (the only way it becomes visible is if you zoom in as far as you can while standing right next to it).
The Mokoko Seed is located at the island's hidden northern entrance (seen in the image above), and the game will prompt you to interact with it long before you ever see it.
Instances of Mokoko Seeds
Off-map locations include the second and third Mokoko Seeds. There is no bouncing yellowish-gold arrow at this wall, but the game will offer you the chance to climb it if you get close enough to it in the middle of the southern strip of the island, as indicated in the left image above.
The seeds are located on the top of a second wall that must be climbed after the first one is reached (right image).
The Fourth Mokoko Seed
Eastern Mokoko Island, where there is a lot of room, is where you'll find the fourth Mokoko Seed. It's tucked away in the shadow of a tree, inside a little bush of purple-red flowers.
Mookoo Seed #5
The last seed is a little further north of the fourth Mokoko Seed, also in the island's east. Be vigilant because it is hidden from view by nearby bushes and is shaded by a nearby tree.