Short answer

The official Grand Blue experience description names fighting styles, weapons and equipment as active systems. Current gameplay also supports a connection between weapons, skills and progression. The site does not yet publish a “best sword,” complete style roster, trainer map, shop inventory, stat table or upgrade cost because those details are not verified to the required standard.

What the evidence supports

SystemStatusWhat to do now
Weapons and equipment existOFFICIALBuild around the items and requirements visible in your own client.
Fighting styles existOFFICIALCompare the live kit against the job you need next.
Weapon and skill choices can be connectedSOURCE-BACKED CURRENTConfirm requirements before replacing a weapon.
Mining can feed weapon progressionSOURCE-BACKED CURRENTMine when it solves a real upgrade requirement.
Full weapon / style roster, stats and costsUNVERIFIED / HOLDDo not treat a one-video shopping route as permanent.

Choose a weapon or style by gap

Your current gapVerify in the live UI
Quest clearing is slowRange, area and usable skill slots
Boss damage feels unsafeConsistent attack window and survival options
Fruit already covers damageWhether the weapon adds movement, control or a required skill route
Upgrade is blockedExact material, tool and profession requirement

Before buying or swapping

  1. Read the live item and skill description.
  2. Check whether your active skills require the weapon family you are leaving.
  3. Inspect the actual material / currency requirement in the client.
  4. Keep a working setup until the alternative solves an identified problem.
  5. Recheck after a patch or shop change.

Why “best weapon” is not published

That claim needs comparable current stats, skill interactions, upgrade costs and test context. Creator opinions are useful research leads, not a durable database row. A false best-weapon page can send a new player into the wrong shop or a bad reroll; holding it is the better answer.

Use Skills & Mastery to verify what a skill source actually proves, and Life Skills when an upgrade path points toward Mining or food / profession work. Use the Build Planner when you need to decide whether a Fruit, Race / Trait effect or weapon should solve the next gap.