This card can only negate the initial activation of Spell/Trap Cards. It can't negate the effect of an already face-up "Royal Oppression".
This effect does not target.
You cannot activate this card if your opponent has no cards in their Deck.
Both parts of this card's effect are considered to resolve at the same time.
If this card is activated as Chain Link 2 negating a Spell or Trap Card, the negated effect will not be resolved, so the Chain is over after the opponent draws 1 card.