What was your toughest boss-battle ever?

This one is from my own personal experience. Do please share yours.

I'm no Souls player but I like a challenge from time to time. With that being said, there's this one mfer that nearly brought me – a 41 year old Amy vet – into tears. More than once. And his name is Svipdagr The Cold – a Berserker in GOW Ragnarok. The reason I had so much trouble fighting him is because he had 2 ***holes with him spamming projectiles from across the arena. I had to beat all 3 of them AND my ADHD in order to win 😆🤣