Watch the ending from start to the end, if not, this trick will not work. You will reach the screen which says 'The End' and you will also hear the familiar Final Fantasy 'Crystal Theme'. Now, input these codes:
R2, L1, R2, R2, Up, X, Right, Circle, Down, Triangle, L2, R1, R2, L1, Square, Square. (Start)
You should hear a chime. If not, you screwed up. After the chime, press the Start button to play Blackjack. If you don't know how to play Blackjack, youre a dumbass.

Jump Rope
The first mini-game that you will encounter in Final Fantasy IX is the jump rope mini-game in Alexandria. To participate in this mini-game, have Vivi approach the little girls who are jumping rope to the left of the ticket booth. This is a good opportunity to get some extremely rare cards, and maybe obtain a key item early in the game.
After Vivi moves over the rope, press the Circle button to begin the game. Each time a '!' appears over Vivi's head, press the X button to jump.
Don't underestimate this game. The speed at which the rope moves increases at 20 jumps, again at 50 jumps and then again at 100 jumps. At 200 jumps, though the speed subsides a little bit, the timing is quite different. From 300 jumps and onwards, the timing remains the same.
You can only win each reward one at a time. Even if you start over and achieve the number of jumps you have made previously, you will not receive the same reward again.
You can play the mini-game at the beginning of disc one to the left of the ticket booth. From disc three onwards, the girls move their games to the moogle's bell tower. In disc three and four, you can only play if you have vivi or eiko in your party.

# of Jumps
10 Gil
Cactuar Card
Genji Card
Alexandria Card
Tiger Racket Card
King of Jump Rope
# of Jumps

Nero Brothers Gambling
At the beginning of disc three, enter Alexandria's weapon shop with Zidane. You can only play this mini-game when you are playing as Zidane, not Vivi. You will find the Nero brothers, Benero, Genero, and Zenero in the weapon shop. The mini-game resembles the nut in a shell game. The three brothers will shuffle their positions and after shuffling, they will ask you to identify one of their brothers. If answer correctly, you can choose to continue on the game or receive your reward. However, if you identify wrongly, you lose everything. The answer's either left, center, or right. The only reward you get is gil and you can max it up to 25,600 gil.
The further along in a game you get, the quicker the brothers shuffle. After about the fourth 'continue' in the game, they get insanely fast. As a tip, make damn good use of the Start button to pause midway through a round after your eyes start to blaze.

Racing Hippaul
This mini-game is a good opportunity to get some rare cards, as well as getting a key item. You can only take part in this mini-game with Vivi at the beginning of disc three when you are in Alexandria. Note that if accept to see Ruby's play in disc three, the mini-games, including racing with Hippaul will end. So, accept Ruby's request only after you have played the mini-games.

You can find Hippaul and his mother on the main street of Alexandria. Speak to Hippaul's mother and agree to help Hippaul to cut down his weight. Hippaul is too damn fat. Thus, a race with Hippaul starts. The basic premise of this minigame is simple. All you must do is alterantely tap Square and Circle as quickly as possible. The faster you do, the quicker Vivi runs. You can and should start mashing the buttons before Hippolady actually says "GO". This ensures that you start as soon as possible. When you do it slowly, each press of each button corresponds to one stride of Vivi's legs. However, when you tap the buttons very fast, the length of Vivi's strides increases, rather than the amount of strides. If you press either Circle or Square two or more times in a row, Vivi's stride will severely shorten until you get back into the groove of the alternating Circle, Square, Circle, Square.. The race ends when both reaches the finish line.

Hippaul's level will increase when you keep racing with him. The higher his level is, he runs faster. For every 10 levels that Hippaul gains, his mother will give you a card. You can keep winning a card until level 70 and at level 80, you receive a key item. The maximum level Hippaul can reach is 100 but you won't get any reward when Hippaul is above level 80. So, stop when Hippaul is level 80. Here's the reward:
Hippaul's Level
Wyerd Card
Carrion Worm Card
Tantarian Card
Armstrong Card
Ribbon Card
Nova Dragon Card
Genji Card
Athlete Queen
Hippaul's Level

If you get the Athlete Queen, the Mognet letter in Treno that says: "There is a new champion sprinter in Alexandria. His name is Hippaul!" now has Vivi's name, rathe than Hippaul's. Just a little something extra, but not useful.

Treasure Hunting In Fossil Roo
On your way from Fossil Roo to Outer Continent in disc two, you might come across a cave, where a treasure hunter awaits. I don't think there is a need for me to describe the cave in details since if you explore Fossil Roo carefully, you should be able to find the cave. It's the place where there are a lot of Gargants, and enter it through Qu's Marsh in the Mist Continent.

To play the game, talk to the treasure hunter. He says that he will let you dig the rocks here if you give him a Potion. Agree to his request and he will give you a pickaxe.
You can dig in any area on the top or bottom portion of the central column. At the top portion, there is a wall that seems to be made of loose walls. Be sure to examine them. Press the Square button continuously in an area until you find an item. All the items you find will be yours. In this digging game, you will find many Ore, rare stones, and medicine. Also, this digging game has no time limit. Return the pickaxe to the treasure hunter by talking to him only when you wish to quit the digging game. If you return the pickaxe to him, and later on you feel like playing the digging game again, you have to give him a potion again.

If you play the digging game, you may come across an area where you hear a sound called 'Kupo'! Isn't this the sound made by a moogle..? Does that mean that there is a moogle nearby? Damn strait. You have to dig on the furthest right top portion of the cave area to find the moogle. The name of this moogle is Kuppo. Kuppo will give you the letter which you need to deliver to Kupo, so, don't skip him!