Robo is one of the most important worldwide NPCs, Being the only one which allows you to set your spawnpoint in the current island you are.
There is not much to say, its function is self-explanatory and also the "why" it is in the game, mainly to settle on an island, for grind levels, farm bosses, etc. allows you to avoid the tedious work of going from one island to another to do the farming thing (most of the time).
However, if you decide to be a marine, this NPC will not allow you to establish spawnpoints on certain islands, apparently for reasons of giving the game more fidelity compared to the anime (?)
ROBO'S ISLAND LOCATION[]
| Island | is there? | Marine Friendly? |
|---|---|---|
| Town of Beginnings | Yes | Yes |
| Sandora | Yes | No |
| Shell's Town | Yes | Yes |
| Zou Island | Yes | Yes |
| Baratie | Yes | Yes |
| Orange Town | Yes | Yes |
| Mysterious Cliff | No | - |
| Roca Island | Yes | Yes |
| Colosseum | Yes | Yes |
| Sphinx Island | yes | Yes |
| Arlong Park | Yes | No |
| Kori island | No | - |
| Land of the sky | Yes
(3 locations) |
Yes |
| Gravito's Fort | Yes | Yes |
| Fishman Cave | No | - |
| Fishman Island | Yes | Yes |
| Marine Base | Yes | Yes |
| Coco Island | No | - |
| Reverse Mountain | Yes | Yes |
| Rovo Island | No | - |
| Desert Kingdom | Yes
(3 locations) |
Yes |
| Sashi Island | Yes | Yes |
| Spirit Island | No | - |
| Colosseum of Arc | Yes | Yes |
| Foro Island | No | - |
| Thriller Bark | Yes | No |
| Rose Kingdom | Yes (3 locations) | - |
| Transylvania | Yes | - |