imprisoning mirrors

so two very common cards in the game are shadow-imprisoning mirror and light-imprisoning mirror Both are really popular side decks as they shut down a lot of decks but some people mistaken how their effects work so I am basically going to go over it and use two examples of an effect a trigger effect and a continuous effect

Before i start if you don't what the mirrors do here's there effects:
Shadow-Imprisoning Mirror (Continuous trap): Negate all DARK monster effects activated on the field or in the Graveyard.

Light-Imprisoning Mirror (Continuous trap): Negate all LIGHT monster effects activated on the field or in the Graveyard.

As you can see they clearly have the same exact effect except one affects dark's and one affect lights. So lets go over how they work. Both cards negate the effects that activate on the field and graveyard. Good examples of cards negated would be caius, the shadow monarch and broww, huntsman of darkworld (obviously attribute matters here, just going using dark monsters for this). Caius effect goes off the moment it is summoned and activates on the field. Due to this, shadow mirror would negate its effect. Broww activates once discarded from hand to graveyard and activates in the grave, due to this shadow mirror would negate this. Now going against a card like Battle Fader or Honest is a ruling commonly messed up by a lot of people. Both of these cards are effects that activate in the hand and due to that the mirrors can NOT negate their effects. So lets review what was just said, both mirrors only negate effects that are activate on the field or in the grave and cannot negate effects activated in the hand.

Now, we've just talked about a couple of trigger effects. Now i'm going to talk about facing a continuous effect one of my favorite effects to look over is Evilswarm Ophion. Here is his effect (I'm going to highlight the part we are looking at)
Evilswarm Ophion:2 Level 4 lswarm monsters
While this card has Xyz Material, Level 5 or higher monsters cannot be Special Summoned. Once per turn: you can detatch 1 xyz material from this card; add 1 infestation spell/trap card from your deck to your hand


His effect that makes it so Level 5 or higher monsters cannot be special summoned so this happens to be a continuous effect. Now some of you may be asking why does this matter Well its because shadow-imprisoning mirror only negates effects that activate, so how can it negate an effect which does not activate? Continuous effects do not start a chain and are just conditions on the field. This means they do not activate which means that the mirror cannot do anything to them due to wordings. This basically means that shadow-mirror and light-mirror are 100% useless against monsters with continuous effects and players usually think they can negate those types of effects.
from (akatsuki) grov from EDA