There is no current way to get Empty Soul Vessels, the 2 ways to fix this are: To make the world boarder bigger. Or to add a crafting recipe. Likely a good recipe to use would be:
X X
X Z X
X X
X is Oneironaut's Hex-Warded obsidian, and Z is Oneironaut's Wisp Rangerler.
There is no current way to get Empty Soul Vessels, the 2 ways to fix this are: To make the world boarder bigger. Or to add a crafting recipe. Likely a good recipe to use would be: X X X Z X X X X is Oneironaut's Hex-Warded obsidian, and Z is Oneironaut's Wisp Rangerler.