Cool topic.
I started gaming in 1982, so I grew up thinking games were
supposed to be hard and that was normal. As a result I beat a lot of games as a kid I wouldn't have the patience for today. I plan to do a top 10 hard games I've beaten for this topic, explaining why they were hard for me, and how I overcame them. That'll be later when I have more time.
What's interesting to me is most of the games mentioned so far, for the ones I have beaten, I didn't consider particularly hard at the time. That's not braggado, just shows we all have different ideas of what's hard and not hard. So to briefly talk about games mentioned that I've also beaten...
>Batman
The only difficult part of this game for me was Joker. I beat him by being extremely aggressive, without trying to dodge.
>Batman Returns
I beat the SNES version of this, not sure if that counts.
>Brandish
I beat the PSP version of this, it was kinda tough. Not sure how it compares to the SNES version's difficulty.
>Castlevania III
Depending on the character and routes taken, this game can be moderately difficult or very difficult.
>Comix Zone
Beat this so long ago I don't recall much about it now.
>Contra
I think this game is so well balanced that its difficulty is overstated. Doesn't take long to get really good at it.
>Mike Tyson's Punch Out
The only hard part of this game for me is Tyson. He is definitely a difficult boss. That said, I beat him using a software emulator (Mesen) on a Dell Windows 10 laptop with an LCD screen and a USB controller (Buffalo SNES). So I disagree that you need a real NES and real CRT to beat this. And I beat it
legitimately too, didn't use save-states or cheats. You just have to learn to anticipate Iron Mike's moves (there are tells) and react preemptively.
>Ninja Gaiden
The only hard part of this game for me, are the damned troll hawks and the final boss. The final boss is BS until you learn its pattern.
>Phantasy Star II
This is not a hard game except for the overtly high encounter rate. That's the only real negative I'd assign to this otherwise stellar JRPG.
>Super Castlevania IV
This is one of the easiest games in this series.
>Super Mario Bros 2 (Japan)
I beat the FDS version of this. And it's fairly difficult, yeah. Basically a mean ROM hack of the original SMB. But like every other "hard" NES platformer, it's just a matter of memorizing the levels/enemy placements and relying on muscle memory. With games like this you have to ask yourself how much of your free time you're willing to give up, in order to memorize the layouts. Being a static experience it isn't as difficult as games which have dynamic content are.
>Tactics Ogre: Let Us Cling Together
I beat the PSP version of this. Very easy SRPG until you get to the "Hanging Gardens" section, wherein the difficulty spikes. But how big a spike depends on how much you've grinded your levels to get that far. If you purposefully grinded your levels will be high enough that the HG section won't be so dramatic. If you played very strategically and get through the game quickly as a result, then you are punished at the HG section because your units will be low leveled, facing brutes that require high level attacks to kill. I had to go back and grind my units to handle the HG section and it really soured TO for me as result.
>Vagrant Story
This awesome game is only as difficult as the player's understanding of its blacksmithing system.
As
toei said, I think this really depends on your starting character (and partner character). Try solo-ing
The 7th Saga as Lejes and get back at me.