Combat is simple: How you fight. More so on with what you fight with rather than how you actually take down a person. There are a few different things you need to know about Combat while out and about. While in regular missions, you can use combat in anyway you want. Say you are skilled in using guns but you run out of ammo. Now you have no way to shoot people right? And you have no other proficiencies in order to really fight. Well, not to worry! You can do just about anything you want in a thread. You see a melon? Yes, that is your new weapon. Congrats! Just chuck it! No one really cares! It is really only in the missions that it comes down to an issue. And even then, it is not a big one. As you have noticed, each weapon is in a tier. To gain a weapon, you must be proficient in some kind of combat if you wish to use that weapon.
Example: You have found a rather nice sword. It is a Tier 2 weapon and has the ability to add a Tier 0 attack along with it every other attack. Nice right?! Only problem is, you are only proficient in Guns. That's a real big bummer! But, not the end of the world. While on a mission, you have the chance to roll an Unproficient Die to be able to use that weapon you found. Only way to use it is if you get a Success or Critical Success. If you don't, you are stuck playing with whatever weapon you have that allows you to punch really hard at whatever Tier you have it at.
Another thing that you have seen is Magic. While I will explain more on Magic in a moment, for right now, let me explain how Magic works in combat. Someone who is skilled with magic may use magic. However, if someone wants to use it to fight with, you must have the Talent "Battle Magic" in order to use your magic in battle on a mission.
In a regular thread, you may do whatever you wish with your magic while in combat.
Simple yes? Alright. Let me just list a few examples of combat talents for you all:
Small Sword expert
As you can see, there are many different kinds of combat Talents. The only thing I ask you to do is not to add too many weapons into one sub category. There are many different kinds of weapons out there and each category is equally just as hard to learn as the other. You can't expect someone who has a Black Belt in Karate to have a the same understanding as a Black Belt in Taekwondo as they are two different fundamental teachings. The same could be said for people who know how to use a Hand gun and then having a sniper rifle being trust upon them.