ERM means Event Related Model and is dedicated to Heroes of Might and Magic III: Shadow of Death game and add-on. ERM is a new technology that makes possible dynamically changing the map objects' properties as a result of certain player's (including computer) actions. It essentially offers scripting (programing) posibility. Some default script files ensure WoG enhancements as described in the latest version info, but ERM also gives the basic game user access to creating its own scripts to add his own imagination and flavor to the game.
In earlier versions, there was no network support (only single player and hotseat) but now WoG fully supports Network play including TCP/IP. The only exception is that scripts dealing directly with battle commands may not function correctly in a human vs. human battle online, however there are ERM commands now to check and adjust or disable the script accordingly.