Do you wince when you see a 15-lb "greatsword"? Do the "warhammer" pictures in D&D draw a groan? Are you ok with the idea of a dark lord with a fiery sword, but insist those spikes must mean -4 Reflex save vs Web? Or are you just curious about how a knight really could beat a dragon, especially if he had one of Pegasus' relatives to help? If so, this may be the thread for you.
If you also want your players to make dysentery checks on a three-months caravan journey, this thread may not be serious enough for you.
In short, this is a thread about the fun kind of realism. That is, "like reality, but with Orcs, Dragons, and variably subtle wizards, and without the boring/aggravating parts." Of course, everyone has there own ideas about where those lines are, but that's the beauty of discussion: We can always learn something.
And I'll start off with a ramble.
This is a posthumous picture of *"Lucas Cranach the Younger - Prince Elector Moritz of Saxony" with what we can probably make a good guess is his favourite weapon: A warhammer. https://upload.wikimedia.org/wikipedia/commons/a/a5/Lucas_Cranach_the_Younger_-_Prince_Elector_Moritz_of_Saxony_-_Google_Art_Project.jpg Now, one of the things you might note is that he seems to be a fairly big guy. That armour does not have narrow shoulders, and as a **medieval noble, he would be expected to be in fighting trim, and to lead his troops into battle. Which means that suit would be made to fit him very well, or there's a notable chance he'd die and look ridiculous while doing so.
Now, the armour itself looks like it's trimmed with a red and gold paint. That probably was literally paint with gold in it. This isn't just frivolity; it's politics. As a medieval nobleman, a major part of his job was maintaining the dignity, sanctitiy, and international presence of his office and people. Politics ("poly, meaning many; ticks, meaning..." yeah, old joke). Yeah, the system was bad. Within the system, though, his own subjects might rebel if he didn't look the part of their leader. And even today, any international leader who went on TV in jeans and a t-shirt would probably get quite a lot of their nation's own citizens angry.
The painter themselves would not be some poor starving artist. Whoever painted it, very likely had Prince Moritz as their patron, which means said painter (he or ***she) would be wealthy, influential, and likely have !combat training. If you had a social status higher than "sert", you were expected to own and maintain arms and armour of your station. Even peasants were expected to at least train with the bow and staff.
Now, taking another look at that armour, the shoulder-plates are large, but the plating itself is not thick; looking probably no more than three millimetres. This is where the previous note on the painter likely having combat training becomes important; because they'd know how to paint armour, because they'd both seen many examples and very likely owned some form of it. At its thickest, on the very front of the briastplate, the armour would probably reach a whole 12 mm of thickness. Even Gothic plate, made to resist the !!muskets of the day, would not be more than 25 mm on the front, and half that on the back, and less most elsewhere.
The armour itself was likely tempered steel, as seen by the sheen. Tempered steel is pretty close to impervious to most medieval weapons; here we see a Youtube video of an untempered bascinet versus sword, axe, mace, and warhammer: https://www.youtube.com/watch?v=l47Idc7anG4
Notably, even the warhammer falls to make more than a small hole. The main issue would be concussions, spine damage, brain damage, and a broken neck. However, one important note: With the sole exception of that poorly-made war-axe that broke, all of those weapons were the equivalent of side-arms. If you guessed that breaking and getting through armour is what greatswords, polearms, and crossbows were for, congratulations.
Also, a katana is a perfectly good cutting blade that's capable at thrusting, as well; made by a culture whose style of sword-duelling happened to not include cross-guards. It is neither the best nor the worst sword ever; it is simply a sword, and does what it does fairly well.
Now, tear my post apart, and post your own thoughts.
Sources: (Because you should always state sources)
The ARMA (The Association for Medieval and Renaissance martial Arts. Also maintains historical texts on combat arts, of which a precious few survive)
Wikipedia, English.
Youtube:
Scholagladatoria (!!!HEMA instructor. Seems to be good for expert opinion)
Skallagrim (HEMA practitioner/beginner. Has more of a practical view of things, and from the perspective of an enthusiast who's been practising for a few years)
LindyBiege (Archeologist, historian. Seems to have more of a scholarly bent that can miss practical details, IMO)
ThegnThrand (Seem to be amateurs focused on testing theory. Have not seen many videos. Their test of a medieval greatsword vs medieval briastplate was worth more than a thousand words of theory)
* I know nothing about this guy. His picture is on the English Wikipedia page I found on a search for "medieval warhammer".
** If you "learned" about the "Feudal System" in school, you can probably safely forget most of what you were taught without losing actual information.
*** If you also "learned" that women were mostly shut away and ignored during the medieval ages in school, you can generally forget much of that, too.
! So that stuff you may have "learned" in school about medieval knights...I'm sure you can guess.
!! Guns were around as early as 1400 AD.
!!! Historical European Martial Arts