The Layer Cake Challenge for 7 Days To Die is pretty straightforward. Simply start a new Random Gen world with the Biome Layout being set to "Line" and each biome having 20% each. This will generate a map that has all of the biomes in a line from left to right, (which slightly resembles a slice of layer cake) starting with the Forest, to the Burnt Forest, to the Desert, To the Snow and finally the Wasteland.
The premise is simple - You must spend a full 7 days in each biome in progression order. So days 1-7 you will be in the Forest Biome, you can quest and build all you like, but after you've taken on the day 7 horde, you must then move on to the Burnt Forest. You have a grace period until 17:00 the day after the horde to move from the old biome to the new one, allowing for a couple of trips if you need to do that.
It's then essentially rinse and repeat until you take on the day 35 horde in the Wasteland - with each biome having escalating game and loot stages, it should see the challenge and journey to end game ramp up quickly. You'll need to plan your character build and manage building resources efficiently. But you can't be too frugal with the resources, as the further into the challenge you go, the harder these hordes are going to hit.
Days 1-7: Forest Biome
Days 8-14: Burnt Forest
Days 14-21: Desert Biome
Days 22-28: Snow Biome
Days 29-35 Wasteland Biome
Rules:
Permadeath - if you die, the run is over and you'll need to start a new one
Play on whatever settings you're comfortable with, the only real big one is the horde needs to be every 7 days.
You can't go between biomes at all, if you get given a quest in a different biome - tough, you can't do it. The only time you can travel back and forth is until 17:00 on the day after the horde to move between bases.
I thought it made an interesting challenge. If anyone gives this a go let me know how you get on