I would add "Remove the guard" to your list.
top notch tactics

I would add "Remove the guard" to your list.
This is a general tactic and could be achieved with other things already mentioned, such as a decoy.
to OP: I don't think any are 'more important', it depends on the position.
X-Ray: enlighten me? Never heard of that before.
Attraction: isn't a tactic. Baiting someone into making a bad move is not a tactic. Unless that's not what you meant? Forcing them into making a bad move is a tactic; but that's 'forcing play', not 'attraction'.
You missed:
Double Check
Under Promotion
Perhaps you meant to ask what is more important for a beginner to learn first; for an advanced player it's important to be able to recognise all of them, instantly.
If this is the question then the most important to know first are the ones which occur most frequently, as follows:
En Prise
Pin
Fork
... and the others in any order.
Hope this helps
A


I would add "Remove the guard" to your list.
decoy and removing the defender are the same thing.

Tactics are usually a combination of such themes. You can't "know" "pins, skewers" etc. You just get slowly better and better at them by studying.

is double attack considered a tactic.
Yeah.
To the above, decoy and removing the defender are not the same thing.
what are the most important tactics in your point of view list them for instance like 1.pin 2.decoy 3.discovered attack .... and so on here are all the tactics I know
pin
fork
x-ray
en prise
decoy
attraction
skewer
discovered attack
zugzwang
zwischenzug those are just the one's I know but if you can list them from your favorite to least favorite.