Hopefully Zoro. Just look at how big of a boost trading Shusui for Enma gave to Zoro even though Enma is only a slightly better sword. Sandai is two tiers below Nidai, so getting Nidai might be enough to make Zoro YC1 level.
[automerge]1569469557[/automerge]
Checked the wiki and no other Meito has the same pattern as Sandai, Nidai, and Gorosei sword/Shodai
[automerge]1569469557[/automerge]
Checked the wiki and no other Meito has the same pattern as Sandai, Nidai, and Gorosei sword/Shodai

