Synchro Monsters are a type of card in the Yu-Gi-Oh! trading card game. They are special monsters that are summoned by combining a Tuner monster with one or more non-Tuner monsters. This process is called Synchro Summoning, and it allows players to create powerful monsters with unique abilities. To perform a Synchro Summon, the total levels of the monsters used must equal the level of the Synchro Monster being summoned. Once summoned, Synchro Monsters are placed in the Extra Deck and can be used strategically to enhance gameplay. They often have effects that can turn the tide of a duel.