It included "Initial implementation of the character's skill "Immunity"" and various optimization passes. File Characteristics
The .rar extension indicates the file is compressed. You would need a utility like WinRAR or 7-Zip to extract it. Escape.from.Tarko.v 0.12.9.10532.part1.rar
A significant increase in the size of the Woods map, adding new points of interest like the USEC camp and abandoned village. It included "Initial implementation of the character's skill