Angermax, known as Ungarmax in the original release, is Barret's second level 3 Limit in Final Fantasy VII. It causes 18 physical attacks that hit random enemies for half Barret's normal damage each. This causes more hits in a single attack than any other ability in the game.
When using Angermax, Barret will focus on his opponents and then spray 18 shots in rapid-fire towards them.
Angermax is obtained by using Satellite Beam six times. Barret can equip the Cover Materia to speed up this process at any time. For specific grinding, a good spot is the large forest in the Nibel Area past Mt. Nibel where enemies appear in large groups (helping other party members acquire Limit levels that require multiple enemy kills), and their attacks deal enough damage to Barret to raise his Limit gauge considerably. One enemy fought here, Valron, uses Gravity-based attacks that reliably increases Barret's gauge quickly without killing him.
Angermax will fire 18 hits at random enemies, at half Barret's physical damage each, dealing total damage of nine times Barret's normal physical damage, but spread across all enemies. Against single targets, Angermax can reliably deal a significant amount of damage, making it Barret's better level 3 Limit Break against bosses. However, against multiple targets, Satellite Beam is more reliable, and depending on how many opponents there are, can deal more damage overall. Angermax's damage depends on Barret's physical stats, derived from his Strength and equipped weapon.
For most of the game, Angermax is outclassed by Catastrophe, Barret's ultimate Limit Break, which causes 10 hits to random enemies at 1.25 times his normal damage each. This means Catastrophe's damage equals 12.5 times Barret's normal physical damage, compared to Angermax's total 9 times his damage. As such, when obtained, Catastrophe is a better choice for damage.
However, Angermax's 18 hits allows it the potential to be the strongest ability in the game, and at its max potential deals 18 hits of 9999 each. Barret will need his ultimate weapon, Missing Score, with several mastered Materia (such as Knights of Round). Power Sources and a high level can also increase Barret's damage further to help him reach this. The simplest way is to use Hero Drinks whose effect also stacks. Any of these methods can make Barret's Angermax the most powerful ability in the game. Its maximum total potential damage, being 18x9999, is 179,982.