Here is the full list of all 19 Sproggiwood achievements.
Beat Hakkipunki on Savage with every class.
Beat the Bloated Grotto on Savage with every class.
Kill 10 enemies in one turn.
Beat Big Tree on Savage with every class.
Beat Goaturku on Savage with every class.
Beat a dungeon without killing any enemies besides the boss.
Beat Ickykolo on Savage with every class.
Defeat Surma on Normal.
Defeat Surma on Easy.
Kill a bizarro cloghead.
Kill 5 enemies in one turn.
Kill a monster that loves you.
Defeat Big Ick on Easy.
Defeat Big Ick on Normal.
Beat Ignis Caverna on Savage with every class.
Beat Ensi on Savage with every class.
Beat the Floating Isles on Savage with every class.
Beat Uppmas Point on Savage with every class.
Beat the game on Savage with every class.