Here is the full list of all 12 Letter Quest Remastered trophies - there are 7 bronze, 4 silver and 1 gold.
Earn 40 crystal stars
Earn 120 yellow stars
Spell 3000 words
Purchase 30 upgrades
Complete 50 quests
Defeat 250 monsters
Do 100 critical attacks
Purchase 50 merchant items in battle
Open 10 treasure chests
Spell 3 words with no vowels
Use 25 plague tiles
Finish a stage with full health