Image if you will, a marine is in combat without weapons against a skilled unarmed opponent. The closest target area in relation to the arms is the opponent's guard. The Marine ignores the head an body and grabs the guard. In this case the opponent's arms (it could be a spear etc. or any hand weapon held in a guard that is outstretched to the front).
The marine grabs the opponent's arm (snatch, slightly circular punch with open hand), and while most skilled opponent shouldn't have any trouble getting out of a grab, this poor fellow finds the marine is too strong (plus the armoured gauntlets) and they can't twist out of it, the marine's thumb is not weak point in their grip, and the opponent is held fast. (a regular human can use the same tactic but they have to move in while their opponent is defeating their grab, as most human aren't strong enough to maintain an outstretched grab hold around the arm)
The marine crushes the arm in the grab, snapping bones and pulls the (out of range (head/ body)) opponent towards them for a finisher. The marine isn't chasing after their opponents, instead the marines snatch what comes close and drags their opponent to them.
In comparison to a striking style, and in single combat, this is no more difficult than punching at a guard (the most commonly known use I imagine is boxing). Swap the punch impact for an open hand grab. A quick snatch.
When the marine is facing multiple combatants, the same thing applies; snatch and pull. The marine draws people to them to be destroyed. This also deals with over-commitment problem as the arm is much faster and quicker to recover than the whole body - a fast deadly opponent (Eldar/ Nid) is going to find it harder to catch the marine over-balanced. I think marines are very good at retaining their balance (for their size they know it would be a weakness) and rarely overreach or chase their opponents.
As to other techniques used to speed up the butchery, a marine could literally grab the arm, force the person down and knee them in the face or body (about the right (optimal) height considering the difference in size). A bit comical imagining them 'marching' through a crowd like this, but considering their armour it wouldn't be a problem. Using one arm means they can still hold their weapon.
This grab and pull would, as I mentioned earlier, defeat many conventional hand weapons; from two handed swords (with guards such of the plough or ox) and spears, to single handed weapons and shields. It is the marines grip that is deadly, and just like a medieval gauntlet they can grab a 'live' blade with their power gauntlets and not care. They can use one arm to deflect high one handed mace blows and the other to grab their shield and pull the bearer down (the Bolter is heavily armoured and could act as a shield of a sorts). Marines are hand grapple fighters, and this is how I imagine the Techno-Barbarians (makes me think of techno music and barbarians all freaking out at a rave!) of ancient Terra used to fight with their powered torsos - the forerunner of the Mark 1 'Thunder Armour' used by the first marines. A legacy I image would carry over to current marine close combat systems.
In general terms the snatch and grab means no second chances for the opponent to recover. I see marines as being all about the business and they wouldn't waste their strength advantage in combat. It also allows them to grab weapons and turn them on the bearer, in many ways the marines do not need to carry hand weapons into combat because the enemy will supply the levers (weapon) of their own destruction. A weapon is just a way for a marine to get to a person quicker (if the opponent is stupid enough to hang on). Kinda like combat fishing.
I think it is very interesting inventing combat arts for the marine. I believe it's a good idea to draw inspiration from many of the current arts, but not limited by them: think of the possibilities!
Hearing feedback is very important to me in developing my ideas. Much of my designs are inspired, and crafted, by chatting to fans on forums before snowballing into a full concept you'll find here. I would like to thank all those who have contributed critiques and participated in discussions over the years, and I would especially like to thank all those who commented on this specific topic. If you would like join in, you are most welcome!
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