The Imperial Guerrilla Offensive is a series of guerrilla attacks on JSDF conducted by Zorzal's force led by Viscount Herm Fule Maio. In detail of Herm plan, due to the superior firepower of the JSDF in the open field, most of the attacks on JSDF must be conducted through ambushes and guerrilla attacks. The Imperial Guerrilla often conducted based on the pattern that Imperial troops will disguise as civilian and merchant to attack the unsuspecting JSDF troops while Herm and his general from the far distance will send monsters like black dogs or ogres to decimate the JSDF during the chaos since the JSDF will have to busy fighting the disguised Imperial troop. Furthermore, Herm also uses shapeshifters to attack the JSDF while disguised as innocent civilians.
However, due to Herm heavily underestimating firearms and advanced technology together with his hidebound approach in warfare and utterly ignorant about JSDF's logistics and communication, most of the operations have little success and often end in blunders. Despite inflicting some damages on JSDF and sometimes force them to retreats, the Imperial Troops often faces pyrrhic victories since they lose a couple of hundreds of men and black dogs as well as ogres in every operation just to take down mostly 10 to 20 JSDF members. Furthermore, Herm and his troops also lack awareness about scanning technology, resulting in Imperial Troop being rooted out at a fast pace by JSDF since the JSDF can detect them under their disguises through scanners as well as the JSDF has already adapted to his strategy in a short period of time. Furthermore, the shapeshifters employed by Zorzal's forces, despite having the ability to fight quite well and physically superior to a regular human are also quickly killed after facing the JSDF who had more training in quickly reacting to unexpected situations. To make matters worse, Herm and the rest of pro-war senators and general cannot comprehend the JSDF's night vision technology in which they cannot figure it out how the JSDF can accurately take out ambushing troop in the dark night, which leads them to think that the JSDF somehow can see through the dark. As a result, even a night raid and ambush against the JSDF also turns into a huge disaster for the Imperial Troop.
One of the most prominent fatal flaws in Herm's plan is that he never takes into account of air support as well as artillery support of the JSDF in which all his black dogs and ogre are decimated by Napalm and missiles from JSDF gunships when they surround the JSDF platoon. The reason for this flaw is that Herm doesn't grasp the concept of how air bombardment and air supports tactics work in modern warfare since he was too used to melee close combat ambush and dragon riders for close combat support, which was the basis of medieval warfare. Herm also cannot anticipate the ability to adapt to warfare of the JSDF since the JSDF manages to increase their reaction times against Imperial's ambushes after a few skirmishes. Finally, the deadliest error made by Herm is that he has zero concepts of hit-and-run tactic in the basic rule of guerrilla warfare as he often swarm-attack the JSDF and only retreating after losing nearly the entire ambushing troops, making his tactics generally wasteful.
- "Assaulting them with hordes of monsters was not very effective due to the losses such efforts had incurred. In addition, their guerillas’ bases had been exposed and were gradually being wiped out. Of course, they were establishing new bases at the same time, but the rate of construction was roughly equal to the rate of destruction, so they were at a stalemate." — Imperial Guerrilla tactics become a utter failure, depicted in Volume 7, chapter 4 of the light novel.
As a result, the Guerrilla tactics only work for few times and after the incident involving Tomita and his troops' successful anti-guerrilla operation, Herm finally quits his Guerrilla tactics in frustration while learning little from his failures. Furthermore, the use of napalm by the JSDF also causes Imperial soldiers to lose vast amounts of morale due to the horrible effect on their comrade's burning bodies and nothing they can do to extinguish the flame. Unfortunately, the ego, pride and arrogance of Zorzal, Herm and other pro-war senators and generals are too big to see the horrible effects the JSDF inflicted on their own soldiers.
Ironically, while Imperial Army is considered less difficult, the real difficulty for JSDF lies in their own country and its neighbors, when many people like Komurazaki try to cast the JSDF under a bad light for personal purposes, based on anti-guerrilla activities of the JSDF. Neighboring countries are also taking advantage of these activities to press Japan on relevant issues (Gate, human rights,...). However, the JSDF itself - and the supporters - have many ways to prove their actions are right because of their ability to propagandize as well as the support of a significant number of Special Region's residents. In addition, because these campaigns - theoretically - take place outside of the Earth, JSDF can easily evade the strict international law in military operations (For example, the use of Napalm - which is considered a violation of international conventions). Despite that, the JSDF also refrains themselves from using much more controversial weapons like chemical or biological weapons such as phosphorus or anthrax due to the potential political and social repercussion in the international community.
- When captain Himeji explains about the JSDF's skirmishes against Imperial troops's ambush to the international military officials and inspectors, two American military officials imagine the skirmishes to be similar to the problem of Middle East's insurgency and the Vietnam war in which the JSDF is facing like the US in the part. Ironically, they seem to not realize that the Imperial army, Zorzal and his generals are not as formidable or even intelligent and practical as the Islamic terrorists and the Viet Cong, the US had fought in the past and the present, thanks to Zorzal and his cohorts's incredibly stupidity and lack of adaptability in warfare.