Here is the full list of all 26 Delver achievements.
Max out on backpack slots.
Max out on belt slots.
Listened to the wise.
Grab the orb.
Died, for the first time.
Make it through the Ruins
Find 300 gold in one run.
Chow down on 40 things in one run.
Bought something from Joff.
Bought something from the wizard.
Buy a magical elixer from Joff.
Escaped with the Orb.
Take 400 damage in one run.
Make it through the Sewers
Make it through the Caves
Find 5 secret areas in one run.
Identify 5 items in a run.
Zap wands 300 times in one run.
Use 15 potions in one run.
Use 10 scrolls in one run.
Kill 150 monsters in one run.
Become poisoned 10 times in a run.
Buy a belt slot.
Buy a backpack slot.
Make it through the Dungeons
Trip 10 traps in one run.