When Barret performs the Catastrophe attack, he will begin by charging his weapon towards the ground, before jumping in the air, and after reaching a height, fires a huge continuous blast towards opponents. While this blast is ongoing, ten hits will register separately.
Heh! No sweat!Barret
As a level 4 Limit, Catastrophe is learned from a manual after Barret has learned his other Limit Breaks. The manual can be obtained after the Huge Materia quest in Corel by talking to a woman in the ruined building near the inn in North Corel.
Catastrophe performs 10 hits on random targets at 1.25 times Barret's normal damage each for a total of 12.5 times Barret's normal damage. As a physical attack, the damage depends on Barret's Strength stat and currently equipped weapon. Catastrophe deals more damage overall than Barret's other Limit Breaks, but is slightly unreliable against groups of enemies.
Catastrophe is Barret's best Limit Break for most of the game, but can be outclassed by Angermax at its max potential. Angermax performs 18 hits at half damage each, totaling 9 times Barret's damage overall, which is normally below Barret's max damage. However, if Barret equips Missing Score with sufficient mastered Materia equipped, or stat-maxes Barret with sources or Hero Drinks, and Angermax's attacks deal close to 9999 damage, it will deal more damage overall than the Catastrophe. For most normal playthroughs, however, Catastrophe will remain Barret's strongest Limit Break.