Galbadia Garden (Disc 2)
Choose your party members and then hit up the save point. Your first task is to locate Fujin and Raijin.
Head down the right corridor and then continue into the crevice on the right to find some stairs. Go up the stairs and up towards the second floor and you will see Fujin and Raijin standing there.
Talk to them and then head down the left pathway. Go through the door on the right to find a student who has the Card Key .
Now go back down to the save point near the entrance.
Head to the left this time and down the corridor, then take the door on the left. This door required Card Key  and will now be unlocked. In the mouth of the hockey goal crease you will find a Protect draw point. Head in behind the other end of the rink and then make your way through the doorway. The doorway on the right (the opposite side of the corridor that you came from, as well as the opposite side of the doorway as the hockey rink) and find another Male Student who will give you Card Key .
Now go back to the stairway where you first found Fujin and Raijin. You can find a shorter path by heading south (towards the camera) when you leave the room with the second Male Student. The door will unlock as you touch it now that you have Card Key . Go all the way south one more time to find yourself back at the entrance and from here you should remember how to get to where Fujin and Raijin were.
When you reach the stairway again you should head up to the third floor. You can now use Card Key  to unlock the door at the top. Follow the pathway down and jump into the leisure area with the courts.
There is a draw point containing Shell along the pathway at the back. Continue heading to the left through the hallway and into the central Hall in the middle of Galbadia Garden.
As you reach the Hall you will notice a large creature sitting in the middle of the light beam at the center of the room.
That is Cerberus, your new Guardian Force, and you will be fighting him shortly. Before you do though, wander around to the front entrance to where the save point is located and use it.
Boss Battle: Cerberus
Time to do battle with your next Guardian Force. Cerberus is immune to Wind attacks and absorbs lightning attacks so be sure to remove those magic’s from your Elem-Attacks before you start the battle.
One of the downsides and upsides to fighting Cerberus is that he has Triple magic. The downside is that he uses it on himself to perpetually cast 3 magic spells at a time. The upside is that you can draw Triple from Cerberus if your characters do not have it, and because it is such a powerful spell I highly recommend drawing it if you can withstand the damage that Cerberus does.
Not much else to this fight. When you beat Cerberus you will also receive the Cerberus Card.
Make your way to the left (south-west) from where Cerberus was standing (west).
As you walk down the hallway take the door to the left and speak with the Female Student to receive the Card Key . Take the Card Key  and head back out into the main hall where you fought Cerberus and go through the exit at the top-left side of the screen and head up the stairs.
Head left and into the elevator.
They put the save point there for a reason! Save!
Boss Battle: Seifer
There really is not much of a strategy required in order to beat Seifer. He does not hit hard and he does not have a lot of hit points. Seifer is also susceptible to all kinds of status effects such as Darkness, Silence, Sleep, Drain and Gravity.
Edea will disappear through the floor so you will not get to fight her just yet.
So where do you find the Auditorium? As mentioned, the Auditorium is directly below the room you are in, but getting to that room is not as simple as it would appear.
Take the elevator back down to the main floor. Go straight to the right, bypassing both the stairs and the doorway and into the main hall but on the upper floor. This is the same hall where you found and fought Cerberus. Work your way all the way around the upper portion of the main hall and through the door at the southeast side into the auditorium.
Just to make sure that you are prepared, you need to draw a new Guardian Force from Edea called Alexander.
Do not forget to draw Alexander! You will not get another opportunity to pick up this Guardian Force until the very end of the game.
Also make sure that one of your characters can use Mug on Edea.
Boss Battle: Seifer
Seifer is going to give it one last kick at the can. First you have to take down Seifer before you can move on to Edea. Seifer is just as easy this time around.
Boss Battle: Edea
Make sure that the first thing you do is draw the new Guardian Force, Alexander, from Edea the first chance you get.
Make sure you also Mug Edea to pick up a [Royal Crown].
Edea, like Seifer, is susceptible to Sleep. If you junction Sleep magic to your Status-Attack you will make this boss fight incredibly easy. As an added bonus, if you added Sleep Status-Attack to the character with your Mug ability you can keep using Mug while simultaneously putting Edea to sleep until you pull off a successful steal. Additionally it makes the entire battle mind-numbingly easy.
Be careful of her Maelstrom attack that reduces the HP of each party member by half. Edea is also prone to casting status magic which can be removed using either the Esuna spell or a Remedy item.
Time to watch some videos at the conclusion of Disc 2. Moving on to Disc 3!