The Mysterious Merchant is a traveling merchant. He appears in certain towns at random (often Sailor's Island) and offers to sell certain items, he has a very distinct Asian look, which as his name implies makes his presence a bit mysterious.
Once they have been downloaded, players can buy the Tuna Cutlass and Swirlmerang from the merchant in the Dreamcast version. In the remake, players can buy Vyse's Sky Fang from the merchant after they attain the rank of Vyse the Legend.
The following is a list of confirmed places where the Mysterious Merchant can appear.