Here is the full list of all 44 Trials of Mana achievements. It takes around 50-60 hours to unlock all of the achievements on Windows.
Become a master magician.
Become a master thief.
Become a master guard.
Complete Angela's story.
Complete Hawkeye's story.
Complete Riesz's story.
Complete Chapter 6.
Defeat Archdemon.
Find Li'l Cactus in all possible areas.
Complete Chapter 5.
Accumulate at least 100,000 lucre.
Open 200 treasure boxes.
Complete Chapter 4.
First ride on Flammie.
Complete Chapter 3.
Complete Chapter 2.
First ride on Vuscav.
First class switch.
Open 100 treasure boxes.
Complete Chapter 1.
First cannon ride.
First encounter with Li'l Cactus.
First time learning a chain ability from an unexpected acquaintance.
First time learning a companion's chain ability.
First time learning an ability.
First time planting a seed.
Obtain all achievements.
Stop the end of the world.
Play with all six main characters.
Complete Duran's story.
Complete Kevin's story.
Complete Charlotte's story.
Purchase nitromyte for the listed price.
Accumulate at least 500,000 lucre.
Learn 20 abilities as any character.
Learn all abilities as any character.
Defeat Anise on hard.
Defeat Mondoragon.
Defeat Dark Lich.
Defeat Black Rabite.
Become a master swordsman.
Become a master fighter.
Become a master cleric.
Max out magic pot level.