Super Mario 64 DS?

Game #12

Hint 1: In this sequel your goal is to make sure that the event you were trying to avoid in the previous game happens. In both games your goal is the same (save the World), but your information varies. In this sequel you finally visit places that you had only heard before, including a lost continent named after a group of Primates.
Hint 2: The previous game in this handheld RPG franchise has already appeared in my list.

Hint 3: The franchise has had 3 entries at the moment.

Hint 4: Yo may remember this game advertisement, it featured Edvard Grieg's most famous song

Hint 5: (Can't be so difficult!) The developers of this JRPG are also famous for their work in sports game featuring a famous italian character.

Hint 6: This is the second game in a franchise with 2 entries, all of them on handhelds: the first 2 in the GBA, and the last one, that hasn't had a sequel although it ends with a cliffhanger, in the NDS.

Game #9:

Hint 1: This RTS may be too obscure, specially outside some European countries, so I'll give abundant information: It was developed by a Romanian studio, that would later develop two entries in the Tropico franchise. The title of this game varies from country to country: In Spain the subtitle made reference to the Latin name of the country, in Italy to Carthage, in the UK, both to the celts and Carthage, while in the US it made reference to the Roman Empire. Those four civilizations (Iberian, Celts (or Gauls), Carthage and Romans) were playable in the game.

Hint 2: The game is set in the Punic Wars and was launched in 2003. It's the second game in its franchise, and its predecessor was set in the Gaul Wars.

Hint 3: It's an RTS, but its core mecanic depart from the usual of the genre: there's no resource gathering nor building construction, it has some RPG traits and soldiers need food to survive.

Hint 3.2: In the US, the name of this game changed drastically from its predecessor (it was similar to the UK one).

Game #7:

Hint 1: Not sure if it's the longest, but this adventure is a great journey (and no, the game is not Journey).

Hint 2: Two worlds are going to collide in this Point & Click adventure: one is futuristic and tech-heavy while the other is fantastic and based on magic.

Hint 3: The game has had a sequel, but it departed from the C&P genre. It would later release a third sequel in episodic format that was partially financed via kickstarter.

Game #5:

Hint 1: This game, second in its franchise, would popularize a certain strategy sub-genre that has been mastered by certain swedish publisher. Paradoxically, this publisher's stocks are listed in New York.

Hint 2: Ka-pi96 had the developers right: those are the guys that made Crusader Kings, but this game is previous (although the time setting is inmediatly posterior).

Game #3:

Hint 1: Mario Kart 8, in the 15th place of my list, is my favourite Mario Kart game. But it's not my favourite racing game. If you've been following my list, it should be clear which game is this.

Hint 2: Is not only a racing game, but a karting game.

Game #2:

Hint 1: Raccoon-dogs can fly and shift into statues. Normal raccoons can only fly.

Hint 2: Third game in the series, many people considers this or the next game (that would release in another console) the peak of its genre.

Game #1:

Hint 1: I'll let you guess

You got all three of them right!

Good guess, but nope.. I already have the og Mario 64 on my list.

5: Europa Universalis maybe then, but I'm not sure about the release-timing compared to Crusader Kings

3.Diddy Kong Racing?

2. Super Mario Bros. 3

1. lol uhh. Well, gonna go with the one that's generally (like, in the world) viewed as the best one then I guess. Ocarina of Time?

Really have no clue on your 12 and 9 lol.

Mario Kart 64 as guessed by mZuzek

'Mario Kart 64' is the best game in the racing genre ever made to me. I guess probably this is debatable and objectively not so quality-wise in today's world, even in it's own series, but to me, it undoubtedly is. This is because of what it did back in the day as a game, and what it meant to me as a gamer, or bigger yet, as a person. Because of the amount of time I spent with it, the memories attached to it and certainly also the amount of fun I had with it.

The formula of the 'Mario Kart' series, should be familiar. Being among the most successful series in gaming, there's probably not a lot of people who haven't played one of these games at least once, and even less that never heard of it at all. In this case, the game features the classic four cups each with four courses and each playable character has it's own themed course among them. With racing skill and the help of both offensive and defensive items the player attempt to win first place, and the Gold cup after four races.

This game is legendary in my family. Many years ago, when we were all still together, we would all participate in tournaments. My parents, two of my cousins, my aunt and uncle, and me. Grandmother was always happy just watching in the background. At one time though, my third cousin was actually present. A rarity. It was the last time I ever saw him, as family perils and other drama broke up much of the family. I remember it like it was the day before yesterday: My mother and stepfather were Peach and Yoshi respectively, like they always were. My cousins were Donkey Kong and Toad like they always were and my third cousin took up Luigi. My aunt was Wario, she usually won, contrary to my uncle, who was Bowser and always got the Lightning power-up for being in last place. And I, I was Mario. This game? This game means family, and memory. Memory of lost loved ones.

#8: Considering the date, that's in the name of the game, the theme and the architecture, I'm pretty sure this game is about a golden period of my country, even though it's never mentioned or hinted at.

#11 - Okami

I've wanted to play this game for a long time, and I finally got it earlier this year. It's longer than I expected (and to be honest, wanted), so I haven't finished it. Nevertheless, it's a fantastic game. Takes place in really ancient Japan, and it practically tells the tale of the country's mythology. The art style is nothing short of glorious, and to this day the graphics hold on really well. The music is a little mixed for me; I'm not very fond of the random Japanese "Kyoooh"s or the weird guitar/banjo tunes. However, there are some fantastic songs in the game (look up Shinshu Field and Ryoshima Coast right the f now).

Even though the story is... well, history, it's presented in an amazing way. Funny, witty, and bold are some ways of putting it; we're dealing with Japanese here, specially since it is mythology. So it's nice to see it being written in a non-serious way. And the gameplay is also great, although a little tedious at points. The wrost part about it I would say is that it can get boring for long stretches, which is one of the reasons I haven't finished it, but once I start playing it I go for hours.

Amaterasu's main weapon and power is her god-brush or whatever. She can do anything by drawing in the world: slow down time, refill destroyed objects, bloom trees, control fire, water, wind, etc. This makes every part of nature, including other creatures (in combat, this is important) useful. 

Finally, the main reason this game is so high is for its world and all of its content. Unlike most *cough* 3D Zeldas, the overworld is actually interesting and filled with things to do. It feels very much alive, and heck you're mission is to make it even more alive. Feed animals, fix buildings, bring nature back, solve issues. It all feels connected and meaningful. And another thing I like about it is the independance of dungeons. Unlike Zelda, where the majority of puzzles, action or gameplay take place in a dungeon, which in my opinion are very abundant, Okami has very few dungeons. You don't just go to a town, get in the dungeon and leave. You explore the world, go back and forth between towns and the overworld, and ocassionaly get to a new dungeon. That makes each dungeon more valuable, since they're so rare.

And with that, I think I've made the longest post in the thread... I can beat it with #9

Hint #10 - I dont know how. It's a 3D DBZ game.
I'll just outiright hand it to you guys: DBZ: BT2

Hmm

#10 Ori and Blind Forest? 

#9 Metroid Prime

#8 Portal 2?

I just finished the 2nd part, after cleaning the green smoke in the city.

It could go up a few spots, but I'm 16 hours in and only missing 2 brush techniques (I think?), so I feel I got enough out of it already. Heck, I said it's longer than I wanted it to be. I also watched a full playthrough some years ago, so I knew I would like it a lot.

I finished my #1 game in only 12-14 hours, and it was a 100% run. I'm growing to a point where I want my games shorter. But funnily enough, I want my #4 game to be longer... it'll make sense later...