Tuner monster

Tuner Monsters are required for the Synchro Summon of a Synchro Monster. When the total Level of the Tuner monster and the other monsters on your side of the field matches the Synchro monster's Level, by sending them to the Graveyard, you can Summon the Synchro Monster.

Tuner Monsters are the first secondary Type of Normal Monsters, and the fifth secondary Type of Effect Monsters, like Union and Spirit Monsters. Subsequently, there are some Tuner Monsters which are Effect Monsters (e.g. Krebons, Blackwing - Gale the Whirlwind or Junk Synchron) and a few that are Normal Monsters (e.g. Water Spirit and Tune Warrior). Furthermore, there are cards that can treat non-Tuner monsters as Tuners, including themselves (e.g. Lightwave Tuning and Tuned Magician). As such, Tuning is NOT considered an effect, and cannot be negated with cards such as Skill Drain and Junk Synchron.

Most Tuner Monsters are low in Level, usually ranging from Level 1 to Level 3, but they often have effects that allow them to facilitate the summoning of a Synchro Monster, such as Summoning other monsters, altering their own Level, or preventing themselves from being destroyed. There are rarer Tuner Monsters that are Level 4, and currently only two level 5 and one level 7.

There are a few support cards that specifically deal with Tuner Monsters, including "Revival Gift" and "Quillbolt Hedgehog", which further aid in setting up a Synchro Summon.

Some Synchro Monsters require a specific tuner monster (like Junk Warrior requires Junk Synchron and the other Warrior synchro monsters). Others require a tuner of a specific type, Attribute, or Archetype (like Blackwing synchro monsters requiring a Blackwing tuner).

Tuner monsters, like their name, have ties to sound. As such, most support cards have references to music and wavelengths (such as Frequency Magician). A few Synchro Monsters and Tuners also have mechanical appearance, despite not being classified as either machine or psychic, furthering this connection to sound waves.