Ren

Find Ren and start the Lost Nichirin quest

Search around Butterfly Estate for Ren rather than expecting him to stand beside one training station. Speak to him at character level 75 and check that Locate Ren's Lost Nichirin appears with a blade-finding step and a later return step.

Follow the active marker across the nearby river and up the far bank for the missing blade. Once it registers, return to Ren and confirm the return objective completes.

Use gourds after the return

A completed Large Gourd use adds 300 Slayer Progress. Check your current progress before buying more so you can budget Wen for your next weapon or quest.

1. Check that Ren's quest is complete and the gourd training interaction is available.
2. Buy a manageable number of gourds, equip one from Inventory and perform its use interaction.
3. Open Player Info / Progression to check Slayer Progress after the use; a purchased gourd sitting in your bag has not trained you.

Ren's route to Breathing Boost

Slayer Progression level 4 unlocks Breathing Boost. Character level 75 opens Ren's quest, but it is not the same counter as Slayer Progression, breathing mastery or weapon mastery.

On PC, equip a katana and press N after the unlock. If nothing happens, inspect the Slayer Progression reward and your equipped weapon before returning to the lost-blade search.

Watch Ren and the gourd unlock

The video shows Ren’s lost-Nichirin tracker, the return dialogue and later gourd training. It does not prove a fixed blade coordinate or that Ren is always standing in one place.