to edit the packet version
/// Do NOT edit this line! To set your client version, please do this instead:
/// In Windows: Add this line in your src\custom\defines_pre.h file: #define PACKETVER YYYYMMDD
/// In Linux: The same as above or run the following command: ./configure --enable-packetver=YYYYMMDD
#define PACKETVER 20170614 //packet version here
and your error is coming from battle.cpp :))