Whispike Survivors - Sword of the Necromancer

These four achievements all require the same thing, they just use different maps and they each have different times you need to survive. They range from 5 minutes on Forest to 12 minutes on Ravine. Once you survive the required time, the Necromancer will show up and kill you. The achievement will unlock after you're dead. See below for help to be able to survive the times.

Forest Survivor (80G)  Alas Forest - 5 minutes
Volcano Survivor (80G)  Mount Lisad - 7 minutes
Cave Survivor (80G)  Suib's Maw - 9 minutes
Ravine Survivor (80G)  Raen's Ravine - 12 minutes

Again, see Attack on Whispike (90G) for the farming method I used to get a lot of abilities on a custom/hybrid whispike to start each map. Once you farm a bit to get 10 abilities, and get some levels in the abilities to start maps, getting to the different times will be a breeze. Just follow the farming and use the manure to get each seed to an adult until you get 10 abilites with some good levels and you're ready to start each map. Just try to get to when the chests start to spawn and then further level your abilities by winning the slot mini game. Don't worry though. If you die before getting to the Necromancer you can just re-plant your seed and use more manure to get most of your abilities and levels back to try again. Do be aware though if you make it to the time limit and the Necromancer kills you to get the achievement you will lose that seed and have to start the farming again to do the next maps.