A support card is any card that specifically supports one or more other cards. The most obvious example of support is for archetypes, but support cards may also provide support for Attributes, Types, or monsters with a certain Level, Rank, ATK, or DEF, among other groups of cards.
- "Harpie's Pet Baby Dragon" provides support for the "Harpie" archetype.
- "Barrier Statue of the Torrent" provides support for WATER-Attribute monsters.
- "Magician's Circle" provides support for Spellcaster-Type monsters.
- "Advanced Ritual Art" provides support for Ritual Monsters.
- "Amplifier" provides support for "Jinzo".
However, a card's effect mentioning one or more cards or groups of cards does not automatically mean that card supports the mentioned card(s); for example, the effect of "Acid Rain" destroys all Machine-Type monsters on the field, making it an anti-support card instead.