We noted that some materials come from the crabs in the exploration map. However we found that not all players have crab in their maps. Some players even got zero since the game updated, while some players keep catching them in every trip. I understand the crab is rare, but can you please treat us fairly? We are disappointed about this. Please fix it. Thank you.
Its not that the crab is rare, there's a bug that causes it not to spawn for many players after defeating it for the first time. The crab was tied to the Jolly Ship during last years Christmas event, and many of us could not complete one of the quests because of it. Midoki has announced plans to fix it edit: link to post Missing crab monster
I have a similar problem with one of my max star Serpents, one day after fighting him he never re-spawned, that was months ago. I now only have 1 max Serpent.