[Destiny 2] Proving Grounds Grandmaster boss fight is way easier than you think

I'm in love with this Nightfall. Way too much fun playing it as a Titan.
Tips on Perfect Guarding, guard right as the boss about to stomp you, that is, when his foot is at the peek and ready to come down and stomp you, guard. Given enough practice, this can be easily done.
Also, don't forget to put on Concussive Dampener and Melee Resist.