| Tuner monster
|Japanese (kanji and furigana)||
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 a few that are Level 5, one Level 6, one Level 7, and one Level 8 Tuner.
Some Synchro Monsters require a specific Tuner monster (like "Junk Warrior" and the other "Junk" Synchro Monsters that require "Junk Synchron" as a Tuner). 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.
There are also Tuner Synchro Monsters, which have the ability to Synchro Summon during your opponent's turn, except "Life Stream Dragon". They are also required for Accel Synchro Monsters, such as "Shooting Star Dragon". Only "Formula Synchron", "Life Stream Dragon", and "T.G. Wonder Magician" have been Released.