Itīs not quite detailed explanations but it isnīt a guide ya know . . .
Quetsacotl
The Giant Thunder bird will you get before going to Fire Cavern
Shiva
The queen of ice is back, now with even less clothes, also gotten before Fire Cavern
Ifrit
Ifrit will join you and Quistis in the Fire Cavern after an easy fight
Siren
This half woman-bird can you draw from Elvoret, the big boss in Dollet communication Tower
Diablos
The Dark-Messanger lives in another dimension just use the magical lamp you got from Cid.
Be sure to save first.
Use Demi and he should weaken.
Brothers
In the Tomb-of-The-Unknown-King go to the right and then fight Sacred, the go as left as you
can get and lower a switch. After that go up (follow the map on square) and lower another
switch. And now at last go for the Brothers straight up to middle from the entrance.
You will have to fight them both on the same time but it is "no pro bro".
Carbuncle
Draw him from one of those two bosses that are guarding Rinoa in the Presidential Palace
Leviathan
The legendary sea-monster of the bible can be drawn from Norg when his shell is gone
Pandemonia
The master of wind should be drawn from "Commander" Fujin in Balamb
Cerberus
This Hell-hound with three heads is lurking in Galbadia Garden when the big SeeD battle
is going on
Alexander
The great robo-knight of Holy can be drawn from Edea in Galbadia Garden
Doomtrain
You will need the Solomon ring that will be found at tears point Check Worldmap
and six Remedy+ (use alexanders ability for better medicine and refine 60 Remedys) and six Steel Pipes Check parts
Bahamut
The noble Dragon from the seven-heavens is quite tough to get: At the Deep Sea research center
walk forward to the blue canister, but only when lights is out. Click when standing forward it
A voice will talk and you should click to fight (Canīt remember details) and a ruby dragon
appears and you must defeat it. After that the voice asks you if wanna give up. Click "no"
(canīt remember exactly)and once more a ruby-dragon will appear. When the voice is asking you
next time click triangle and the pointer will move to an invisible answer. Click and and after
some talking from the voice you will meet Bahamut the noble Dragon.
Cactuar
The biggest 1.000 needles of them all is running around "Cactuar Island"
Tonberry
Go for Sentra Ruins and kill 20 Tonberries. On the 20 the big one will appear.
Donīt worry, you donīt have to killīem all in a row
Eden
Well what should I say the FFVIII "Knights of the round" can be drawn from
Ultima weapon that exists deep down the research center.