Please mention your own favorite examples. The most notable difference between bosses IRL vs in games is that in games you generally get to beat the absolute tar out of them. No particular order.
T. Rex, Jurassic Park, Nintendo Entertainment System
There are lots of T. Rex in games, but this one eats children.
Gilgamesh, Final Fantasy V, SNES & various ports
Personally love womping on a bootlicker, and G here is a best in show of the breed.
Super Drunk, Bubble Bobble, Arcade & NES
This guy is kind of making fun of the drunks at bars where this game debuted, which is kind of mean, but as a character he is terrible and I relish in his destruction.
Deerhaunter, Timesplitters Future Perfect, Playstation 2 & Game Cube & Xbox
Because he is also playable, "The Moose is Loose" became a common call on game nights in the mid 00s (especially in Ohio).
Decoy Octopus, Metal Gear Solid, Playstation & PC
Controversial because he cannot be beaten without a multi-tap and "foreknowledge" aka you have to actually read the manual where it suggests you might need to read some Cold War history, plug in a multitap and do CQC on him during a cutscene.
On NES I enjoyed the boss fights in :
Metroid, Kickle Cubicle (my #1 NES game), and Festers Quest
SNES :All of the MegaMan X games and Secret of Mana, Mario World
N64: Mario 64, Conkers Bad Fur Day,
Kickle Cubicle was high on my list of "was that game hard AF or was I just a kid"
I'm pleased to say that as an adult, I did a hell of a lot better at that game!
...fuck everything about Milon's Secret Castle, though...
I was an snes kid, so I never played that one and was blissfully unaware of its existence until I saw that review...
https://m.youtube.com/watch?v=kMz7JkVplpM
Oddly enough, of all the avgn videos that I watched, this and the battletoads one really stuck with me.
Hahaha same here. Yet still an enjoyable game. My brother's and I never got far in MSC.