It sounds like you have just started playing the game.

I am assuming you are referring to Invader Material Equipment  only,  but if not, the simple answer for this is no, nor for normal equipment either.

You actually don't need any of them to play the game , but they all help to do whatever you choose to do in the game better.

For example, If you never attack anyone, why would you need the gear designed for attack? 

There is another post on the forum where someone took the trouble to collate all the information together, but its only really the same information you can get within the game,by looking at the forge information.

Each piece of equipment you can make helps with some specific aspect of the game, in much the same way as researching  knowledge does..

You could choose to wear ALL the Lynx or  ALL Saracen gear all the time, but this would restrict other aspects of the game and  wouldn't mean you would be guaranteed to win any battle  

Then you are in deed  very fortunate if you have everything possible.

As I said in my first answer there is no  absolute guarantee that you will win a battle whatever you are wearing, the opposition could have done more research, have better gems , and runes and a shaman now they added these two.

Your opponent could also be smarter than you in battles, and there's always bonuses that can be used.

If you attack ,they could be reinforced, if they attack they may be able to send enough better troops to beat you ,or even onslaught you.  

I think that you were probably right in your initial  thinking  that,  the Lynx and Saracen  gear are the best things to wear if you are in a battle, but you wont always know that this is going to happen will you?

If you are attacking someone that's fine, but out of the city yeilding, you cant suddenly swop what you have .

I've seen top players wearing a combination of items, or also the full sets of both .

And of course now, that there are Strongholds , there is special equipment  you can forge which is even better than invader equipment.

Sorry I wasn't more helpful or encouraging enough.

It wasn't initially clear to me how advanced you are.

I am surprised no one else has bothered to answer, as yet.

YES,  as you  say, increasing skills in the oracle will add more bonuses which can only help you .

Some of the basic  equipment has high values, so I suppose it is possible it could win in a battle against invader equipment, but as before,. its down to what research has been done on either side and actual game experience.

Sounds like you are in a clan,  if so ,why not test things amongst yourselves. 

I do test as much as possible, & usauly lose for now, but i will fight on & i will complete the huge task plarium has set me 

 thank you for your reply, which kingdom are you, mine is selgearsod maybe we will meet soon...

 my next forum will be joining another kingdom 

You are in a much older Kingdom it would seem .

As you seem to be loosing against live players, and assuming you haven't already done this, here's an idea for you.

Try finding some long inactive players , you should be able to win against them, look at the battle reports and it will show you what your standing is compared to the opponents , might give you an idea why you loose,against active  players and what you might do about it.

Also forgot to mention this before, UBERS new gems are very useful as  they have different  and more powerful  bonuses.