$ sudo apt-get update
$ sudo apt-get install realtimebattle-common 

realtimebattle-common is installed in your system.

Make ensure the realtimebattle-common package were installed using the commands given below,

$ sudo dpkg-query -l | grep realtimebattle-common *

You will get with realtimebattle-common package name, version, architecture and description in a table

realtimebattle-common package basic information: