This only applies to characters that have completed White Plume Mountain at a time where returning the 3rd weapon would reward the character with their choice of Wave, Whelm, or Blackrazor when they reach Tier 4.

Original Guidance from ALAG 3.1

Originally, when your character completed White Plume Mountain, they get an “IOU” for one of the three legendary weapons when they reach Tier 4.

From the Adaptation Guide 3.1:

3. Third Weapon Returned. Each character receives either a blessing of protection or a blessing of weapon enhancement (player choice) and when the character gains 17th level, can claim one of these legendary items for their own use.

(bolding mine)

However, this no longer applies because Wave, Whelm, and Blackrazor are now Artifacts in the 2024 D&D rules. Which leads to…

New Guidance in ALAG v2026.2

The new guidance for completing White Plume Mountain is as follows.

ALAG v2026.2 (page 22):

Third Weapon Returned. Each character may choose one Magic Item Replacement from the Artifact options (any rarity), in addition to one Blessing of Protection or Blessing of Weapon Enhancement (player choice).

When you complete White Plume Mountain, you’re directed to ALPG v2026.2 (page 6):

Magic Item Replacement. […] the item’s an Artifact, replace it with one Boots of False Tracks; Cloak of Many Fashions; Silvered Weapon; Pearl of Power; Bracers of Defense; Armor, +X; Wand of the War Mage, +X; or Weapon, +X of the same or lower rarity.

So, you can now pick one of:

• Boots of False Tracks;
• Cloak of Many Fashions;
• Silvered Weapon;
• Pearl of Power;
• Bracers of Defense;
• Armor, +3;