Diego de Grandepiedravigilante is a military leader of the Second Great Monster Empire, Army General, stone warden , Commander of the Fourth Ground Army. Excellent artillery specialist, artillery forces commander, siege master, specialist in storming fortresses.

Came from the Great Deep Dark Stone Kingdom, he took part in the war against the human kingdoms of the Unknown Lands in which he successfully commanded an artillery regiment

He was a participant in the PMC World War, during which he proved himself to be a talented artillery commander, his artillery units distinguished themselves in the battle of the Eastern District.

After the collapse of the First Great Monster Empire, in the universe of General Schtormand, he joined the GME Legion and took part in the Imperialstoneland's war against the Quartzmajestica Kingdom.

Participated in the Battle of the Quartzheartstone River, led the Siege of Quartzstrongstone Town. Successfully led the assaults of several Quartzmajestica's fortresses.

After the formation of GME 2.0 he was appointed to the post of commander of the Fourth Ground Army