Boss fights can make or break a video game: get them right and they can deliver thrilling and creative moments that players won't ever forget, but get them wrong and they might cause players to quit the game altogether.
To be clear, this list isn't simply concerned with ludicrously difficult bosses, because as we all know, challenging boss battles can be tremendously satisfying (Metal Gear Solid 3's The End, anyone?).
But we're looking at boss fights that, through a combination of irritation and dullness - often with a high difficulty thrown in - left players feeling defeated and miserable.
Whether recurring bosses that made players groan every time they showed up, or final bosses which ensured the game ended on a depressing low, each ran the risk of permanently damaging an otherwise entertaining gaming experience.
Above all else, they're proof that not every video game out there actually needs bosses, and if you're going to do it in 2019, at least try and be a bit clever about it, yeah?...