Here is the full list of all 34 Final Fantasy VIII Remastered achievements worth 1,000 gamerscore.
Beat the Omega Weapon
Kill 1000 enemies
Complete the PuPu side quest
Complete the Obel Lake side quest
Draw magic 100 times from draw points
Defeat every member of the CC group
Lose a rare card in a Triple Triad game
Unlock Guardian Force Doomtrain
Reach maximum HP
Finish the game
Unlock Guardian Force Eden
Unlock Guardian Force Bahamut
Unlock Guardian Force Cactuar
Capture a Chocobo
Find Ragnarok
Collect all Timber Maniacs magazines
Play Triple Triad
Unlock Guardian Force Alexander
Unlock Guardian Force Cerberus
Unlock Guardian Force Tonberry
Unlock Guardian Force Pandemona
Upgrade your weapon
Unlock Guardian Force Leviathan
Reach SeeD rank A
Unlock Guardian Force Carbuncle
Unlock Guardian Force Brothers
Get your first salary from SeeD
Unlock Guardian Force Diablos
Unlock Guardian Force Siren
Kill 100 enemies
Unlock Guardian Force Ifrit
Draw (Stock) magic from enemies 100 times
Unlock Guardian Force Shiva
Unlock Guardian Force Quezacotl