Here is the full list of all 18 Half dead achievements.
Discover five thousand rooms
Discover two thousand rooms
Find a thousand traps
Discover а thousand rooms
Find five hundreds traps
Discover five hundred rooms
Find two hundred traps
Discover three hundred rooms
Find a hundred traps
Discover a hundred rooms
Find fifty traps
Find thirty traps
Discover fifty rooms
Find fifteen traps
Find five traps
Discover ten rooms
Discover five rooms
Find a trap