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