Final Fantasy IX

4 Ways to Get the Robe Of Lords:
First way to get it is to play the Chocobo's Hot and Cold game and earn 10,000 points and redeem the points for Robe Of Lords by talking to the Mene the moogle

The second way is to go through the Stellazzio: Zodiac Coins sidequest. Give the 12th coin to Queen Stella and you will recieve a Robe Of Lords as your reward

The third way is to beat Hades and gain access to the Legendary Synthesis Shop. You must have a White Robe, a Black Robe and 30,000 Gil to get a Robe Of Lords.

The fourth way is to steal using Zidane. Bosses like Ozma and Hades carry a Robe Of Lords. Equip Zidane's Master Thief ability, which can be learned from using Thief Gloves (which can be bought in Treno's Auction House) and Bandit ability, which could be learn from Mythril Dagger. Equip the N-Kai Armlet to ensure that Zidane has a good chance of stealing successfully.

Getting Excalibur:
Just buy the Magic Finger from the Treno auction and give it to the old man in the Dargeleo Library. Sell the rare items you bought from the auction to the people of Treno.

Getting Excalibur 2:
Get to the final area and beat hades under 12 hours. After that, search the right pillar in the Memory Room.

Alternate Ending
You have to finish the Stellazzio (Zodiac) Quest and keep "Shina's Hammer", which you find in the room after fighting Lich on disk #4. Don't lose, use, or sell/combine the hammer. It has to be present in your inventory for you to get the alternate ending.

Coffee Quest
Give the guy at the Watchtower in Dali the three coffee beans he wants
and he will give you the Prima Vista figurine.

Here is where you find the beans:

Pass near the Chocobo Forest, around the right side of the screen.
In the Madain Sari kitchen Disc 3, before finishing the Card Game (While you're waiting for King Cid) head to Dali and check the Chief's hut for a key to the previously locked door inside the windmill.

Stellazzio Quest
Talk to the lady in the house north of the Treno Combination Shop. She will tell you about a set of thirteen Stellazzio that are spread across the world. Find them all and she will reward you everytime you return. This quest is required if you want to see the game's alternate ending.

Here are the zodiac locations:

Aries: Dali; In the windmill all the way to be back (not downstairs)
Cancer: Burmecia; behind the overturned cart
Scorpio: Quan Cave spring
Gemini: Fountain at the first screen after you enter Treno; throw coins
thirteen times into the fountain.
Taurus: Treno; behind the item shop.
Virgo: Black Mage Village Inn; around the beds
Libra: Madain Sari fountain
Leo: Alexandria (after raid); Left Tower near Neptune Statue
Sagittarius: Linblum; in the left side of the 3d screen up of the
Commercial Square.
Capricorn: Dargelo Library; right hand side
Aquarius: Ipsen Heritage; right hand pillar at entrance
Pisces: Treasure chest inside Invincible.
13th Stellazzio: Return to the Quan Cave that's east of Treno after collecting and returning all 12 coins.

How to change the costumes:
When you are in the ice cavern and you beat the giant monster that the little man summons without using magic the man will give up and he will give you an item and run away. Now go to deli village and in the hotel you can get changed in to a different costume.

Black Jack mini-game (Japanese version):
At the end of the game where the "The End" screen appears, press R2, L1, R2, R2, Up, X, Right, Circle, Down, Triangle, L2, R1, R2, L1, Square, Square. You will hear a sound when entered correctly. Press Start to start playing the game.