Megaarmor

The combat armor (also known as blue armor or megaarmor) is a powerup that appears as a blue breastplate. When collected, it increases the player's armor to 200%. It cannot be collected if the player already has 200% armor.

Combat armor will absorb one half of all damage received (rounded down) until it is fully depleted. If the player is damaged such that there are fewer than 100 points of combat armor, then picks up a security armor powerup, the combat armor will be replaced with security armor (and thus absorb only one third of the damage received); thus, it may be wise for the player to avoid certain security armor powerups. If the player picks up a standard armor bonus, however, his armor will remain as combat armor.

Combat armor is not included in the items percentage displayed at the end of each level.

Appearance statistics
The IWADs contain the following numbers of combat armor pickups:

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