Took me some attempts to get my loadout right. My main loadout for this fight was Elemental Materia fused with lightning for Cloud and Barret set up as a healer using Prayer Materia and Big Bertha gun. Also both characters equipped with Raise materia to revive and barret having Heal Materia linked with Magnify so he can Heal both characters with a single cast. The idea was to use Prayer as the main source of healing for the party, since it only uses ATB bars and wastes no magic. You run out of magic points very fast on Hard since you cannot use items. Other than that use cloud to attack the boss's rear when he has his barrier up and lightning magic when possible, especially when the boss is up on a wall. Punisher mode works well and spamming Cloud's triple and infinity strike abilities. Use Barret's overcharge and fire constantly to build up his ATB gauge quickly and have prayer and healing spells ready. Dont use him for alot of attacking. Barret excels at healing since he recharges ATB so quickly with overcharge. Hit triangle when you run out of bullets and Barret reloads to cancel the animation and get an extra charge in.
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