In The Lord of the Rings: The Return of the King Deck-Building Game, you take on the role of Frodo, Legolas, Aragorn, or one of their brave and heroic allies in the struggle against the forces of the Dark Lord Sauron! While you begin armed only with the courage of the free peoples of Middle-earth, you will add new, more powerful cards to your deck as you go. Your goal is to defeat the deadly forces that serve Sauron as you make way towards Mount Doom to destroy The One Ring.

Each player takes on the role an iconic hero from The Lord of the Rings: The Return of the King including Aragorn, Éowyn, King Théoden, Legolas & Gimli, Frodo & Samwise, Merry, or Pippin. Each hero comes with a special card unique to that character and usable only by that player.

Each player starts with his own basic ten-card deck and draws a hand of five cards each turn. Power is the currency you will use to buy new, stronger cards to add to your deck. The goal of a deck-building game is to craft your personal deck into a well-oiled machine with the six types of cards that can be acquired: Enemies, Allies, Artifacts, Maneuvers, Fortunes, and Locations. When a player has amassed enough Power, he may defeat more powerful enemies from the "Archenemy" deck, including Shelob, The Witch-King, and the Eye of Sauron! Each card acquired during the game has a Victory Point (VP) value with the Archenemy cards providing the most VPs. In the end, whoever has the most VPs wins.

Whether played on its own or combined with the other LotR deck-building games from Cryptozoic, The Lord of the Rings: The Return of the King Deck-Building Game introduces a new feature to the game: a map of "The Journey of the Ring". Can you deliver The One Ring to Mount Doom, then destroy it? Some of the cards you play will move the Ring of Power towards Mount Doom on the map, while the minions of Sauron will delay the Ring on its journey. If you fail to destroy The One Ring, Sauron may be too powerful to overcome...