"Link" (リンク Rinku) is a series of cards related to Link Monsters. They appear in Yu-Gi-Oh! VRAINS, where they are used by Yusaku Fujiki (Playmaker), Ryoken Kogami (Varis), and Theodore Hamilton (Soulburner).
The "Link" series is composed of Spell and Trap Cards that support Link Monsters. Nearly all monsters in this series are Cyberse monsters. The exceptions to this series are "Predaplant Heliamphorhynchus" (a Plant monster) and "Lancephorhynchus" (a Dinosaur monster), due to their naming in the OCG. Since the series supports Link Monsters (and to a degree Cyberse monsters), this is not an issue.