I know the plot had explained why people don't use guns anymore. But I think there's still a possibility to reintroduce guns to this world. I'm not trying to change the plot. The plots make sense and I appreciate you put so much thought into it. I just want to give some new ideas while still following the rule of this world.

So the main reason is because guns/bullets are uneconomical against monsters right? But I think they can still be effective against human enemy. Human don't respawn and not everyone can afford magic armor. An non-enchanted bullet can still penetrate physical armor easily, making it ideal against bandits and hostile soldiers. (ie. The human nobility who want to overthrow Ryen with human soldiers) 

Also, remember when Ryen said "We can't raise a huge army overnight"? Well he can if he adapt guns! Guns don't require years of practice or magical study. A farmer who's never touched weapons before can be trained into a decent musketman in just a few weeks. This means Ryen can raise a huge fighting force in relatively short time, the casualties can be replaced quickly, and he wouldn't cripple the economy because the conscripts wouldn't have to leave their original jobs for too long. Meanwhile the mages can use the next several years slowly stocking up enchanted bullets to be used against titans.

This could open up lots of things, such as new Musket Commander who want to form an "experimental" Musket squad to test out new doctrines, or some new events like the three neighboring human countries doesn't like Central adopting such heretic weapon so Ryen has to run a few quest to solve this diplomatic crisis, or quest like Ryen helps uncovering the secret of those flower crystal so Akai can finally mass produce her Steam Gun (since Ryen had unintentionally secured the production of other materials with his Monster Hall).

-  From a huge fan of your game who's also a gun nut!  :D

I'll go deeper into the topic "guns" with a certain group during Elly's and Ryoko's events later. ;)

I love his Ideas and it well be great to have a Squad with guns

Actually Raph216 that won t be easy for some countries and some other countries will not be able to make magic armor                                                                                                        (dorgania) for example could adapt to magic armor but they will not be able to give the entire army magic armor you must remember that they have the largest army of all the neighbouring  countries plus they could not attack central because of the non aggression pact between the two countries     

As for (amagal) they are very good at magic but they don't have a lot of mineral wealth like (dorgania)or(begus) nor do they have a good economy to hire skilled blacksmiths" In fact i think that amagal could help central in stocking up on enchanted bullets in exchange for minerals and workers to help rebuilding there country

and lastly for (begus) begus dose have mineral wealth and skilled blacksmiths but you must remember there mines are over run with undead and they can't make enchanted armor to cover there army with the current materials that they have plus  the church dose not want to deal with the undead because there using  the undead as an excuse to keep the people in line which will lead to a war between (central) and (begus) which is what i would rather anyway" and after the war ends and (ryen) wins we can get a choice to size power in (begus) or give it to the rightful ruler (Queen jeanne) we can even send (kurohime) to get the queen out of begus because the church started to turn against her 

And if we are going to adapt to guns we can go all the way to have cannons and laser cannons the laser cannons could be powered with magic and to have 50 mages power it up until its fully charged and i think (aki) could help with the building of the normal cannons and the laser cannons the normal cannons can be used on human soldiers just imagine arming every castle and fort in central with cannons there won't be a force that could take on central  and the laser cannons are for titans

sorry to put a lot  of work on u ryen but i really love your work and i believe this game could be much greater than it is now