Counter Traps like Seven Tools of the Bandit and Solemn Judgment can also be Chained to Royal Decree in order to negate its activation and destroy it.

Does Royal Decree negate continuous traps?

In this case, "Royal Decree" is not being Chained to the Counter Trap (the effect of "Royal Decree" is Continuous, so it is continuously applied without starting a Chain Link), so Spell Speeds are irrelevant. ... "Royal Decree" will negate the effect of the Trap Card.

Can you chain Royal Decree to mirror force?

Since "Royal Decree" is no longer face-up when "Mirror Force" resolves, it will not negate the effect of "Mirror Force".