Three of the strongest Alone participants take on a bushcraft challenge devised by one of their own - build an Earth Shelter in three days using just a few surprise tools. It's a showdown for bragging rights between Jordan Jonas (Season 6 Winner), Amos Rodriguez (Season 7) and Lucas Miller (Season 1). Who will build the best shelter and win?

Three former "Alone" participants take on a difficult challenge they've never tackled before: build a Bushcraft Bridge in three days using just a few simple tools. Lucas Miller (Season 1), Callie North (Season 3), and Britt Ahart (Seasons 3 and 5) will compete to show off their skills.

Building a wilderness survival shelter is far from simple, but it's even tougher to keep dry when it rains and smoke-free with a campfire lit; that's the challenge facing former 'Alone' participants Clay Hayes, Jordan Jonas and Amós Rodriguez.

This week's challengers tackle a complicated build - crafting a working oven from all natural materials, like sand, wood and water. Luckily, Callie North (Season 3), Clay Hayes (Season 8) and Amos Rodriguez (Season 7) are all highly-skilled former Alone participants. Can they complete what's normally a weeks-long build in just 3 days and with limited tools? Survival expert Britt Ahart (Seasons 3 & 5) will judge the results.

Expert bushcrafters and former Alone participants Clay Hayes (Season 8), Callie North (Season 3) and Britt Ahart (Seasons 3 & 5) tackle the toughest challenge yet - building a working watercraft from all natural materials. Armed with just three simple tools and a tarp, who will float their way to victory?

A 12-foot-high elevated shelter that's safe from predators, in just three days, with only three tools? That's the tall challenge in store for former "Alone" participants Joel van der Loon (Season 7), Jordan Jonas (Season 6 Winner) and Clay Hayes (Season 8 Winner).