Bloodstone

Bloodstone subbiome has ugly trees and questionable puddles of Blood, which makes this a weird place to visit. Some were once home to life forms much like us... until their experiments wiped them out, leaving behind only gory grossness. Which explains the trees that stared at you. Good times.

Codex description
When wandering a bloodstone world, you'll be reminded of blood an awful lot. Because, y'know...blood pools everywhere. And really messed up looking trees. They are a great way to stock up on several sorts of materials through extraction, though.