[quote=The Red Zephyr]Let it be known that BBeast is my favorite person as of now.[/quote]
From what I've seen of you this is a huge compliment. Thank you.

But I will say that modern firearms are not that unlikely to be around and prevalent (if we gloss over a little of the OP, which I shall cover soon). As Sage said, we have lots of monsters and there's bound to be some insurgent/terrorist group around [i]somewhere[/i], so weapons would not have gone neglected. Of course, the kinds of weapons you, Zeph, mentioned would have been the most common, but as the military of Aeros have deep pockets and a desire for the latest tech they would fund not only the development but also the production of modern firearms. The only way for a gang to get their hands on such weapons would be by smuggling them out of the army, but a large enough group (such as the Blood Saints) would be quite capable of doing that. You might bring up the concern of finite ammo, but bullets are used in simpler weapons and most of the 'modern' weapons would probably be compatible with those bullets. The fact that bullets are propelled by cores here means that only the actual bullet part is needed, so bullets would not have changed much since the flint-lock days.

The important part which you are concerned about (in respect to guns) is why there are so many of them. To reiterate, the military of Aeros have deep pockets and a desire for the latest tech. As such, the military would mostly be well equipped by the time the cataclysm happens, and so would anyone leaching weapons from them.
 
 
 
Rereading the OP, I can see the source of my confusion from before in regard to the nature of firearms. The OP has two partially-contradicting statements about firearms. I can see Zephyr's concern too.
[quote]*The weaponry of Leginia, however, is not as modern. The era of peace that the council brought resulted in an end to the thirst for militaristic advancement. Guns are rare, and function based off cores (most will focus on using a Fire Core to project forward a bullet).
...
-Core Firearms (rifles/pistols): Powered by one of five elemental cores: fire, water, lightning, land, or wind. Water rifles are used by fire fighters. Fire, lightning, and land core rifles are used by authorities/military and fire rounds of the element. Land core rifles shoot strong metals rather than burts of fire or lightning. Wind rifles are usually used in riot control as they have deal no fatal damage, but can create a very strong force by lanching immense gusts of wind.[/quote]
In the first part, it says they fire bullets. In the second part, however, it instead says they fire elements. And, also, it does say 'guns are rare', and that there was 'an end to the thirst for militaristic advancement'. Those two statements have been mostly ignored IC. This ignoring can be rationalised, but it would not be right to let it go unnoticed or let it continue too much.

In the collab, I at least would have expected there to be some mention of core weapons in use if the OP had been at all regarded. I don't see how they [i]didn't[/i] have lightning or fire guns. As we've gone over, the use of the modern guns in that battle can be rationalised and thus doesn't need removal, but for future posts we really should heed the background that has been given.
 
 
P.S. Sage, I have a PM for you.