|“||I'll see you hanged for this!||„|
|~ Admiral Greyfield's catchphrase.|
Admiral Greyfield is a major antagonist in Advance Wars: Days of Ruin serving as the main antagonist of Chapters 11 to 21 of the game. He is the leader of the New Rubinelle Army (NRA) who seeks to conquer the world.
Following the apocalyptic meteor shower that ravaged planet Earth, Greyfield gathered the remains of the Rubinelle military together to form the "New Rubinelle Army". With the army under his command, Greyfield declared war on Rubinelle's age-old enemy, Lazuria.
Greyfield and the NRA soon received backup when Davis brought in Captain Brenner and his 12th Battalion. Greyfield was convinced them that the Lazurian Army had started the war and that it was necessary to defeat them.
With the 12th Battalion's assistance, the NRA was able to defeat the Lazurian Army. However, the 12th Battalion soon learned that Greyfield was the true instigator of the war. After witnessing Greyfield order the execution of the Lazurian commander-in-chief Forsythe, Brenner, and the 12th Battalion turned against him.
Greyfield later killed Brenner by dropping a nuke on him (as well as several of his own troops). However, this didn't stop the rest of the 12th Battalion from pursuing him. He was eventually confronted by the 12th Battalion's second-in-command, Lin who reveals that, despite claiming to be the strongest man in the world, Greyfield was actually a fairly mediocre commander who faked his results. Greyfield was then killed by Lin.
- Greyfield's European name "Sigismundo" is derived from the Holy Roman Emperor Sigismund of Luxembourg.
Advance Wars: Days of Ruin