Here is the full list of all 18 Galactic Wars EX trophies - there are 8 silver, 9 gold and 1 platinum.
Complete all trophies
Lose all your lives before the third wave
Achieve your first perfect wave X2 Score Multiplier
Achieve four perfect waves in a row X5 Score Multiplier
Get your ship to its maximum fire power level and transform a shot orb into an energy one
Get your ship to its maximum missile capacity and collect a missile orbi to shoot them automatically
Continue the game after losing all your lives
Continue until you exhaust all your credits
Get into the original high score table
Complete the first mission with the Vulxen 77
Complete the first mission with the Lexus 69
Complete the first mission with the Gyxuss 82
Complete the first mission without losing a single life
Complete a mission with a Rank B or higher
Complete a mission with an accuracy of 50% or better
Complete the second mission
Destroy the final boss in its hive
Complete a mission without collecting a shield orb