So like I mentioned before, the game will be based on Mount and Blade melee combat system. I like to start off by mimicking the functionality of other successful titles. This is because, well, those games probably did somethings right and and there are merits to their setup, even if it's not obvious at first.
First thing first is the camera. The camera is controlled via mouse movement as what you expect in a 3rd person camera game. A set of direction keys (WASD) controls the character movement. The character can run and walk (guard):
The core of the combat system is very simple. There is attack (left mouse button) and block (right mouse button). There are 3 different attack directions and 3 guard directions. To pick the direction of block, swipe the mouse towards that direction and then hitting the block key(right mouse button).
(Attacks works differently than what the following gif shows, it will always come from the same direction of block rather than be controlled by mouse movement)
The purpose of these directions is that blocks only work if you block the correct attack direction:
Some more "advanced" stuff:
First, you can move during attack/block.
Secondly, you may cancel an attack via guard before the attack is fully committed. This can be used to "feint" your opponent but since online multiplayer is a long, long distance away its more of a "oh shit" thing:
Another concept is "parries." If you time the guard to be as close as possible as the time when the attack swing will connect, there is a greater chance of interrupting the swing. The idea is that there is a tradeoff between safety (guard as soon as possible) vs payoff (guard as late as possible, but possibly missing the block)
And putting everything together:
But who am I kidding, the player is so overpowered against the AI that you can simply do this: