First of all this is Easter Egg, to get this achievement you need to use cheat Konami Code in Mulandir Nexus.
Can be done anytime in game after reaching Mulandir, BUT BEFORE going to Golden Road!!! on any difficulty.
First go to Mulandir Nexus trough world map, than had up near North-West God-Stone and enter Konami Code.
up, up, down, down, left, right, left, right,(arrows on keyboard) B, A (letters) within 10s from entering first command
My advice is to crank difficulty up to Circle Mage
After the Doe is spawned (you'll hear teleport sound) deer will follow Tahar everywhere on map, but don't go far from God-Stone because you'll have to re-spawn deer 2-3times (if you're doing it in late state of game).
Get as close to deer as possible, click on it and click "Delete" to cause explosion.
Just do this until your hero die (and don't revive him, rune will do that).
If delete doesn't work check in settings if that option is pined to that key
Take off your armor to fasten whole progress
PS. you'll get interesting loot (not part of achievement)