In case you’re like me and were confused on what to do for the Caveman achievement or Muck achievement and how you’re supposed to repair the ship to beat the game
The actual explanation
You can ONLY use the rock for ANY damage whether it be a resource or enemy, using any other item/tool/weapon will invalidate the achievement. Getting materials to repair the ship will require you to either find said materials in chests or have bosses break the resources for you (I know for certain that Big Chunk can destroy resources like dark oak trees pretty well, i’m unsure about Gronk’s effectiveness as I haven’t used him yet, and Guardians can damage the resources with their laser attack but it’s not very effective with resources high in health like dark oak or obamium).
Getting the Muck achievement is a similar principle, but much more difficult. Like Caveman, it requires that you only use the rock for damage, meaning you’ll still be stuck using enemies as slaves to gather resources, but at a higher risk because of the potential damage. You also can’t pick any power-ups up or it’ll also invalidate the achievement.
A useful tip just in case
Guardian lasers, Big Chunk’s rolling boulders, and Gronk’s thrown swords can be blocked with walls in case you want to avoid damage or if one of the projectiles breaks through or misses a resource you’re trying to mine
Good luck achievement hunting!