What four bosses are on the Difficult Boss Battles Mount Rushmore?

Board 8

Sans (Undertale)
Geese Howard (Fatal Fury)
Mike Tyson (Mike Tyson's Punch-Out!!)
Malenia, Blade of Miquella (Elden Ring)

The reason for Geese Howard is because he is the birth of "SNK Boss Syndrome." A terrible, terrible disease that has spread to many fighting game bosses such as Rugal Bernstein, Goenitz, and even characters that are not from SNK such as Shao Khan.
Someday, I too will become Florida Man.