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