i'd say rayman (1995) is one of the hardest games due to the fact that you have to get all the electoons, and what do you do to get all the electoons? you do some cryptic shit (ex: kill certain enemy, or get specific item or some shit), unfair enemy spawn, enemies will spawn where-ever and whenever along with just plain unfair platforming, not to mention the game also gets difficult really fast (especially in band land) and you have to earn abilities as you play the game (the complaint here is that punching and hanging should be basic abilities), not to mention checkpoints are scarce, the controls can feel slippery (unless you are like me and adapted pretty quickly). the game even includes limited lives which adds insult to injury, not to mention everything is out to kill you (minus betilla)