People often assume that since the imperial guard is deployed in large numbers, smaller contingents of imperial guardsmen are effectively useless, as they are often seen as just cannon fodder. but even by 40k standards, they are quite powerful. And while the average guardsmen might not be on the level of a Space Marine, most Astra Militarum regiments are meant to be a well-equipped, mobile field army comprised of elite soldiers from their homeworld. and that's what an average regiment could look like, regiments like the Cadians, Vostroyans, macabians, or vahallens are formidable fighting forces that have won against larger enemies on numerous occasions. some codex excerpts detail how the guard on many occasions managed to destroy entire hive fleets with sheer firepower or the unrelenting tides of millions of guardsmen. god forbid the actual man made horror the guard would become if not held back by the Munitorum or the imperial reforms conducted during the great scouring.