#5 Valkyria Chronicles

This is the game that effectively validated my purchase of a PS3 back in the day. Up until the release of Valkyria Chronicles there hadn't really been any games on the console that really made me happy to own the console. Valkyria Chronicles changed all that, and still stands as the second best game of the entire console generation for me. One of the main reasons is that this is the only game I have ever played where a specific moment in the story has made me stop playing the game for a while because of how hard it hit. Valkyria Chronicles is a masterpiece in my eyes, and only a few games have ever risen above it.

Hint for my #4:

The best game of the previous console generation. This game's sequel took an earlier spot on my list.

You read it!

That's the one. 

I Haven't played Demon's Souls yet, and considering my current backlog of games I won't be doing so anytime soon. At this point I'm just hoping they rerelease the game on current gen systems so I have an excuse to get it.

#6 - The Legend of Zelda: A Link to the Past

Another real classic. There's a single flaw, and it's those pesky long monologues, which always give useless information that we pretty much know about.

Besides that, this is a joy to play from the jingle and title screen animation up till the credits. I don't have much to say about it. Level design and world exploration is genious, right amount of sidequests and never unfair difficulty (well, the last dungeon is a little too big and confusing, but a child's play compared to Zelda 1's final dungeon).

Unlike OoT and the majority of its sucessors, the game starts you off right away, with the first dungeon and the sword being just a few minutes in. Dungeons are designed around themes, rather than items you get midway through. And going back and forth between Light and Dark World is a puzzle in itself, which asks you for more exploration, which is always welcome from me. Also knowing when and where to use the Magic Mirror is crucial for the last few Heart pieces, which to be fair can become frustrating. 

But yeah, this semi-open world game asks you to explore and rewards you from it. Clever puzzles and secrets, plus the amazing item selection make it a smooth ride. And the OST is fantastic; the SFX overall are amazing.

Honestly, going from The Legend of Zelda to A Link to the Past, I would say this is the best sequel of all time. It expands so well from it, adds so much but still keeps its roots. It's like a real evolution and progression for gaming.

#5 Metroid Prime (Cause I can't put just the trilogy, thanks Leadified)

*Copy and paste what Slarvax said, again.

Big part of my childhood, the great atmosphere, music, the design of the overworlds, everything left a great impression on me (and PTSD from the Phazon Mines). And just like the rest of this franchise (except Other M) I never get tired of replaying it.

Hint for 5: Brought back an old school Nintendo franchise in full force and had excellent reviews.
Hint for 4: Payed homage to the franchise's roots when the 2 games before it went in a different direction, a direction which helped the franchise grow.

Kid Icarus Uprising

People will know this one, they may not necessarily expect it this high, but they'll know it.

#4: This game was supposed to be made in a style very different to the unique look the final game had, though a remnant of the original vision can still be seen in the form of the intro-cutscene.

Hint 2: Namely the intro cutscene featured sprites formed from pre-rendered 3D graphics first pioneered in another of this company's series, instead of the drawn 2D-ones the game itself has.

It's a tough moment to watch for sure. I think the entire story is excellent, but that specific moment still remains one of the most devastating things I've ever seen in a video game.