diff --git a/amulet/level/interfaces/chunk/anvil/anvil_na.py b/amulet/level/interfaces/chunk/anvil/anvil_na.py
index 57c528dd6..b180bf5de 100644
--- a/amulet/level/interfaces/chunk/anvil/anvil_na.py
+++ b/amulet/level/interfaces/chunk/anvil/anvil_na.py
@@ -537,7 +537,7 @@ def _encode_ticks(ticks: Dict[BlockCoordinates, Tuple[str, int, int]]) -> ListTa
                                 "t": IntTag(t),
                                 "x": IntTag(x),
                                 "y": IntTag(y),
-                                "z": IntTag(z),
+                                "z": IntTag(x),
                             }
                         )
                     )