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