How to Host an FTB OceanBlock 2 Server (NeoForge 1.21.1)

Start with at least 8 GB of RAM. FTB OceanBlock 2 runs on NeoForge 1.21.1 with ocean biome generation, Alex's Mobs sea creatures, and a refreshed quest line all loaded at once, so this is the pack's own recommended floor, not a third-party guess.

Install the pack through a proper modpack import instead of hand-copying a client export. A clean import pulls the correct NeoForge 1.21.1 build and the matching mod and config set automatically, which matters here since FTB OceanBlock 2 is a different sequel from the original FTB OceanBlock (which targets 1.16.5) and the two builds aren't interchangeable.

Watch the console through the first boot and don't touch anything until it reaches the main menu cleanly. OceanBlock 2 generates an entirely open-ocean world with no land, so a broken boot here almost always means a missing or mismatched NeoForge dependency rather than a world-generation problem.

Only invite players once that first boot has finished loading without errors. Everyone starts together on the same small underwater platform with no land to retreat to, so a crash during the opening minutes can corrupt shared starting progress for the whole group.

Take a backup before importing an existing world, updating the NeoForge loader, or changing quest or config files. OceanBlock 2's questing and progression are tuned specifically around the ocean-floor start, so a bad config change can quietly break quest completion for everyone on the platform.