Given by Samael after you defeat him in battle during a New Game + who is most likely the said 'wanderer' as 'The Red Wanderer' is one of his many titles.
|“|| An ancient legend of the makers describes the origin of this weapon thusly: A master smith, proud and vain, met a wanderer who posed him a wager. The wanderer claimed that none could forge a weapon that blended both the essence of fire and ice together in balance. Determined to win this challenge, the smith bent his considerable skills towards the crafting of The Mace of the Everflame. This weapon stands as a testament to that legendary smith's skill, and as a trophy of his victory in the wanderer's wager.|
— In-Game Description, Darksiders II