Megaarmor

The megaarmor (known as combat armor in the manuals) is an item that appears in the Doom games as a blue military vest (while the light armor is green and known as security armor). When collected, it increases the player's armor percentage to 200. It cannot be collected if the player already has 200 percent armor. When a megaarmor is obtained, the game displays a HUD message, Picked up the megaarmor!.

The megaarmor will absorb one half (1/2) of all damage received, rounded down, until it is fully depleted.

If a player that had last picked up a megaarmor is damaged to less than 100 percent armor, then they are able to pick up a green armor. If they do so, the megaarmor is replaced by the weaker armor which absorbs less damage per hit. Because of this, it is generally wise to avoid picking up green armor in this case. If the player picks up an armor bonus, however, the protection of the megaarmor will remain.

This item is not counted in the items percentage displayed at the end of each level.

Data
In classic Doom, megaarmors are first encountered on these levels:

The IWADs contain the following numbers of megaarmors per skill level:

Doom RPG
In Doom RPG, the megaarmor is called a combat suit. It increases the player's armor rating by 50 units.