Green Scourges

The so-called Green Scourges was a series of campaigns fought against various Ork WAAAGHs! that periodically harangue the Aegimius System, the demesne of the Penitent Knights Space Marine Chapter.

First Green Scourge
When a massive horde of Orks under the ambitious Warboss Griggasmasha arose from the Asteria Sub-sector, threatening to spill out to cause havoc in Segmentum Obscurus, the Penitent Knights did not hesitate to heed the call to action. Coordinating with other nearby Imperial forces, Lord Crusader Galehaut Abendor divided off the Greenskin horde to be engaged individually targeted and destroyed. While Guardsmen regiments and other nearby Astartes Chapters dealt with the bulk of the xenos, Lord Crusader Galehaut led the Penitent Knights against a daring surprise attack on the Warboss on while he was trapped on the Mining World Hilsdrad. With over four of the Chapter's Orders deployed during the battle, Griggasmasha's host of Greenskins was decimated and the Warboss was killed by Galehaut himself. And while the Knights could not completely eradicate the orkz, a Chapter Keep was built upon the ground Griggasmasha was slain, named "Greenward Redoubt" in honor of the battle that took place.

Second Green Scourge
Once again the Aegimius System came under siege by a great green tide of Orks in the 40th Millennium, but unlike the previous instance of massive war against the greenskins the Penitent Knights had conducted, they now faced an incredibly dangerous Klan of extremely large Orks. Calling themselves simply "Biggunboyz," the xenos were of great individual stature, and the Klan's leader, a Mekboy named Thulgrom Gravesmasha, was known to be the size of dreadnoughts of the Penitent Knights. Needless to say, this fearsome attribute observed by Planetary Defense Forces defending against the raiding Klan was enough to send for the aid of the Knights. When they had thought they would simply perform a surgical strike to slay the Mekboy Thulgrom Gravesmasha, the Knights discovered that the vile greenskin would be possessed of a mind and managed to hide from the wrath of the Astartes, making instead slowly but surely thin the alien horde, until Thulgrom appeared on the battlefield beside his biggest boyz and wrought havoc on the Penitent Knights' line. Then the Lord Crusader's Knight-Exemplar in their ten blades strength surrounded the monster and fought with their lives, being reduced to four men before Thulgrom was brought low by a power sword through his throat. Their chief dead, the Biggunboyz scattered across the Sub-sector, where they were exterminated by Imperial Guard elements.