A Yu-Gi-Oh! Starter Deck is a pre-constructed deck designed for beginners, containing 40-50 cards, including monster, spell, and trap cards. It provides a balanced, ready-to-play deck that introduces new players to the game's mechanics. Yu-Gi-Oh! products like these Starter Decks also come with a rulebook and game mat, offering an accessible entry point into the Yu-Gi-Oh! trading card game.