WoWDB

Murkalot's Flail is attached to a letter sent to the player's mailbox. It is only mailed once to the player's account,* so whichever character that player logs on first is the character that will receive the mail. The letter and item became available in-game on November 6, 2013, at approximately 6 PM PST.

From: Master Handler Sylvester
Subject: BlizzCon 2013

Thank you for your attending BlizzCon 2013!

As a special gift of appreciation, we would like to present you with this eager little murloc crusader.

May Murkalot lead you to new adventures across the face of Azeroth and beyond!

*Players have reported receiving multiple letters with Murkalot's Flail attached to them to multiple characters. The common link seems to be that these extra letters are sent to the first character logged in to on that specific realm. If the player has characters on more than one realm, the player may encounter this issue. The only thing to do is to open the letter, loot the item, and delete it; Murkalot is limited to one per Battle.net account. On the plus side, the player now has multiple copies of the letter.