Here what i learned playing by my own.
I hope i helped you with this info.
This should improve your chance to win in battle:
When you attack a player by pvp :
After that you press "I" (info) icon in upper right corner as shown in pic and you should get info how much you need equipment to add into your army and allies:
By pressing that you get this:
This items you had filled from beginning of your game.
But now you need to fill and this fields:
Calculations on the battle by pvp by pressing ? (Question mark) Icon
You get info how now pvp works:
And this:
How can i fill those fields fast for the war?
You have 2 options,one is by crafting,one is going to the store you should find this items as
Shoes
Head
Artifacts
Shown in pic:
And this: