I have been thinking about it during the day, and realized that it was probably honor that was the problem.
Plus that "honorable combat" was a poor choice of words and sounds bad.

I've been considering what to change it to, and the answer is Chivalry. War has rules, and how to act. And my faction uphold those tenets.
None of my troops will commit harakiri since they failed their lord and lost their honor. They will however be punished according to the rules of war.
My god can still respect those that value honor.

Also, in the game i base it on this nation does have a lower magic resistance than regular humans. The lack of battlefield mages is also a thing.

Also, my description is heavy on the story and history versions of descriptions.
My troops are "Impervious" to attacks in the same way that 6 foot tall men with full plates and tower shields are. An arrow hitting a weak spot or a ballista bolt hitting home still has the expected effects.
Fighting "fearlessly" was a description vikings, redcoats and many other historical forces shared, doesn't mean they don't feel fear. It just means they are good drilled men, whom are not going to break easily.

Also, my character being "taller than the tallest pine in the forest", i'm gonna go with the forests of my homeland, which are rather stumped.
So he's around 5-6 metres. Still massive, but not crazy.

After all, a good sounding description is better than boring stats and rules? :P
Although i could keep that in the actual posts later....

I'll change the description. I think chivalry is rather different to honor since battlefield etiquette and honorable deeds are rather different.

Just to mention though. In historical pantheons, several gods have shared one or more dominions. Like war in norse mythology. But if we are to keep dominions to single deities, i'm fine with that.