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+# Differences in the ABC format
+
+## `Header` section
+
+- Versions range from `0x6a` to `0x6c` instead of `0xa` to `0xc`.
+- There are four unknown 4-byte words after the command string.
+
+## `Nodes` section
+
+- The section starts with an unknown 4-byte word.
+
+## `Animation` section
+
+- A 4-byte word, always assigned to `0xffffffff`, appears before every
+`nodeanim`.
+- Aside from its position and rotation vecots, every animation item contains
+two extra 4-byte words, apparently always assigned to zero.
+
+## `HitGroups` section
+
+- This sections seems to be an extension to the standard ABC format.
+It is defined by two 4-byte words with unknown purpose.