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