Soul sphere

The soul sphere (supercharge) is an item found in all classic Doom games. It appears as a floating blue sphere with a glassy appearance and a pulsing humanoid face inside. Picking one up increases the player's health by 100 percent, up to a maximum of 200 percent (or 199 in early versions of Doom), and the player receives the message "supercharge!".

At one point in Doom 's development, it was intended for the player to have a limited number of lives. The Doom Bible notes that "the soul sphere contains the life energy of a human soul" (hence the appearance and naming) and that collecting it would award an extra life. That behavior would have made it resemble the 1-up (extra life) powerup from Wolfenstein 3D, which is somewhat similar in appearance.

This item is included in the items percentage displayed at the end of each level.

Data Statistics
The IWADs contain the following numbers of soul spheres:

Doom Eternal
The Soul Sphere returns! It takes a realistic appearance and on touch, recovers your health and armor to maximum. It is first spotted in Exultia, and can be seen in the other maps.

Trivia

 * In a beta of Doom, soul spheres originally gave 100 health and 100 points of armor. It is assumed this armor is green armor due to the amount, acting like a "mini-megasphere".
 * In the Doom RPG, the soul sphere gives the player maximum health and maximum armor, similar to the megasphere in Doom II.
 * The soul sphere in Doom 64 contains a rather wicked looking façade on the soul face.
 * In the Doom novels, the protagonist Flynn Taggart describes the soul sphere as 'a floating blue sphere', and as a creature, rather than an item, that zoomed towards him and burst on contact.