On this page of our guide to Doom Eternal, you will find out more about the blue spheres, also known as blue orbs. You may come across these items in places where you have to fight demons.
An example of a blue orb with a head in form of a sphere is shown in the screenshot above. They are usually found in arenas where large battles take place, or near places occupied by demons. The heads, unfortunately, are not marked in any way on the 3D map, and each of them must be found independently.
The blue orb immediately restores your health and armor. They are restored to the maximum level based on the current hero statistics (for more information, check the How to increase hero statistics?). Thus, it is best to collect the orb if you are on the verge of death or after a huge battle with hellish creatures.
Some blue heads, unfortunately, are in places that are hard-to-reach. They can be, for example, levitating at a high altitude. Always look around, for example, for sticks that you can bounce off, or for jumping pods that can catapult the main character into the air.