Complete save! File 1 is 100% complete with all stages and special features accessible. File 2 has all stages clear in the main game but no heart stars collected, allowing you to re-challenge any of the game's first five bosses as often as you like.
btw i feel this a good time to remind you guys that sea of thieves was made by rare, who also made DKC1-3 and DK64, alongside banjo kazooie and conker's bad fur day