If you want to fight against other players, but don't want to risk losing points in the war, you can choose to go on raids. Raids appear as small icons on the map with another player's name next to it, and can be interacted with much in the same way that towers in the war are.
Rather than war points, raids yield high amounts of resources, and do not punish the player for failing (aside from the gold spent to enter and the troops lost.) Raids are therefore one of the best ways in the game to quickly earn resources for upgrades.
If your raid is successful, you will get a helmet, which is displayed on a counter in the world map. If you get four helmets, you will be allowed to choose a large resource reward from one of three options.