Skill

Skill (スキル Sukiru) is a special rule characteristic of Speed Duels featured in the Yu-Gi-Oh! VRAINS anime.

Skills are special effects that each player can only use one per Duel. Skills may possess a number of effects - like drawing extra cards, increasing one's LP or enhancing a monster's ATK. While still ambiguous, it seems that each Duelist has a unique kind of Skill.