Often used in online games such as Counter-Strike by a leader of a team. It is said to stir emotion, and to drive the team to make amazing comebacks when the odds are stacked against them.
After a member of the team has made a speech, all players normally shout "Grish Uder" or "Grish Úder" or any number of other variations of the spelling.
After this, the players on that team buy Para m249 or other heavy duty gun, and go on a minigun rush.
The term was coined by a Counter-Strike pro player by the name of Anti, who's team won the 2006 Russian CS:S Tournement after playing a game where is team was 4 down.
Anti(Team Leader): So tonight, we will be fighting the good fight....fighting the minigun fight! Against the enemy! Fighting for the cute derogatorys! Grish Uder!!!