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