Synchro Material

Source: Yugioh Wikia

Synchro Material Monsters are Monsters that are sent to the Graveyard as part of a Synchro Summon for a Synchro Monster. The monsters needed are typically any one Tuner Monster and any one (or more) non-Tuner Monster(s) whose combined Levels must equal the Level of the Synchro Monster you are planning to bring out, otherwise, you cannot perform the Synchro Summon. You cannot perform a Synchro Summon using just a Tuner Monster, even if the Level of that Tuner Monster exactly matches the Level of the Synchro Monster you wish to Synchro Summon.

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