Nice thread
@kimono, I can gladly name a few, in no particular order.
Phantasy Star 2

What if I told you there's a JRPG that has a Sci-Fi sword and sorcery setting, a hopeful first half, a depressing second half, an ambiguous ending, environmental overtones, incredibly atmospheric music, and a sudden, irreversible, heart breaking character death roughly a third into the game? Except, NOT Final Fantasy 7, and released in 1989.
Graphically, PS2 was a treat and still holds up to some extent. This was one of the first games (the very first AFAIK) where you actually saw your characters interacting with enemies. No descriptive text, or tiny icons swinging at nothing. Characters attack the monsters toe to toe and change animations depending on the action or weapons equipped, set to a pumping battle theme that was a departure from the forboding
"oh no, you're in trouble" music every other RPG on the planet used at the time.
The music in general is amazing IMO and still stands strong. PS4 took PS2's formula and made it better in almost every way, fixing every one of of PS2's mistakes and laying more goodness on top, but it couldn't top PS2 in the music category.
Phantasy Star 2 has a lot of issues. The dungeons are poorly designed and virtually impossible without a guide book (which they included), it's super grind heavy, and the characterization is kind of empty to be honest. Yet it paved the way for others to take the reins and build on its ideas.
Nei crawled so Aerith could walk.
Shinobi
Shinobi took the already tired platform tropes of its day and turned them on their heads. Water doesn't kill you, bumping into enemies doesn't kill you, and the shooter part is actually a red herring. Up till then platformers came in three flavors:
- The Mario, where you basically had no offense at all outside powerups.
- The Contra run and gun, where you had shooting, but were helpless up close (usually just dying if touched).
- The Rygar, where you only had melee and access to anything ranged was limited or non-existent.
Shinobi gave you a mix of all three, with bumping into enemies, unlimited access to long range, and powerful melee up close. That sort of attention to detail simply didn't exist at the time. Make the ninja a little less generic by keeping him unmasked, throw in some amazing music and stage design, and you get a winner that holds its ground against not only other IPs, but its own sequels (many being amazing in their own right).
This is the game that got my little kid self drawing characters instead of fantasy aircraft, eventually building on from there to my work here in the community.
Dungeons of Daggorath

THE most atmospheric game you will ever play - full stop. I can't even describe the genius behind this. It's a massive multi-level maze presented in real-time first-person wireframe 3D, filled with creatures, items, magic and lore. Released in 1982, on a TRS-80 of all things, packed in less than 16KB of space - far less than the screenshot takes up. The game uses an audible heartbeat to monitor your condition, and this alone pulls you into the experience in a way I can't define. There's use of light (as your torch fades, so does your vision, and you need to find magical light to see certain objects/passages/enemies).
It's also hard. Like, mind bendingly hard. You WILL see the evil wizard taunting you time and again - "Yet another does not return..."
Give this a try on emulation, I promise you will be honest to goodness find yourself nervous and listening for danger.
Final Fantasy 7
Okay, let's get this out of the way. FF7 had to be the most over-hyped game to ever exist. At the time, every magazine, show, review, etc. touted it as the greatest thing since toilet paper. Me? I thought it looked stupid. The Steam Punk Sci-Fi setting was way not my thing, the blocky character models were ugly even back then, and so were those muddy-looking pre-rendered backgrounds.
Then, there's all the JRPG cliches to deal with, like having slapstick scenes and mini games five minutes after one of the most infamous tragedies in video game history. Or the game doing everything it can to remind you of that loss, but the characters themselves never mentioning her again until the very end, giving it a kind of empty and emotionally bereft feeling. The story itself is also annoyingly ambiguous, and horribly translated, leaving us to fill in a lot of things with head cannon.
Yet... at least for me, when I finally got around to playing it a year or so after the hype train died, this was the first time since Phantasy Star 2 that I
cared about the characters. That I wanted more and stayed emotionally invested when it was over and remain so to this day. Enough that that got me into reading fanfiction (yeah, yeah, I know), and whatever other media I could find. Advent Children was HUGE letdown, but the Remake Trilogy has been nothing short of amazing in my opinion, building on the characterization, correcting the mistakes, and keeping the cliche jokes separated from the narrative.
Double Dragon
Good gravy I obsessed over this game as a kid. What else can you say? It wasn't the very first beat em' up, but it was the first one that actually worked, and it codified the very genre that inspired this forum. The one that started it all. The one that walked so Final Fight could run, and funny enough, still has more advanced mechanics and granular detail than most beat em' ups to the present day (fence scaling, carrying/kicking objects, stun-based fighting system, etc.).
I could think of a few more - maybe add later.
DC