Calamity Ganon is very tough and seems to have 2-3 phases. Calamity Ganon is one of the final bosses in Breath of the Wild. Perfect Dodging or Perfect Guarding lets you bypass the shield to damage Calamity Ganon. From Windblight Ganon he gets the ability to shoot a volley of lasers, a blast of wind and the power to create tornadoes. First of all, Bomb/Ancient Arrows will be very, very useful.

For much of the first phase of the fight, Calamity Ganon will employ nearly every signature attack available to the Blight Ganon Bosses you’ve defeated throughout the game. Ganon has taken a grotesque form, appearing in a centipede-like figure, with a large head surrounded by Ganondorf's signature long flowing red hair. In this scene, the four champions will aid Link vs the Calamity Ganon. It is a rather highly emotional scene and not only is the scene enjoyable, but Calamity Ganon will also take a devastating blow. When Calamity Ganon has 25% of it's health remaining, it will surround itself with an orange shield.

Keep at it until Calamity Ganon's health depletes. First, if you have all the divine beast freed you will enjoy a very thrilling and emotional cut scene. Urbosa's Fury can stun Calamity Ganon, damage it, and bypass the shield. This shield stays active while Calamity Ganon isn't attacking. The beast fights with a combination of the attacks used by the blights he created long ago and puts up a considerable fight even against the Master Sword's power. Calamity Ganon is the mastermind behind all the destruction in Hyrule.
Ganon is the main antagonist in The Legend of Zelda: Breath of the Wild and assumes many forms.

You could also use an x3 bow, in order to get that damage really high. The enemy awaits in Hyrule Castle's Sanctum and you should really treat this fight seriously. You can reach the enemy without releasing the Divine Beasts, but that's not advisable. Calamity Ganon draws elements from the other bosses to make a formidable opponent: From Waterblight Ganon he takes the throwing spear attack and the barrage of ice.