Oh I wasn't suggesting he led all of those campaigns personally, but this is how he would lead them, just massive invasions with carnage as his main weapon, I doubt there would be many tactics beyond the basic that Kun would employ, but I would wager that eventually he'd seek out Battle Meditation, something he showed when he empowered all his acolytes before they went on the whole night of the long knives deal.
Seems Mandalore at least has a tactical advantage then. But would he be able to withstand Kun's vicious onslaught?
Now you could easily argue that given the ruthlessness of the enemy, many soldiers wouldn't just turn themselves in because they'd die anyway, but I certainly believe it would demoralise the greener crusaders.
Morale is definitely important. And I believe seeing an army of massasi warriors, bloodthirsty Krath and monstrous terantenek bearing down on you would be enough to demoralize even the most fanatic of warriors. Battle meditation would definitely aid this. Did this happen at all in the Great Sith War? And was he or any of his Sith capable of battle meditation?
And Maaurin actually makes a good point. Kun could infiltrate Mandalore's forces, board his flagship and kill him while Mandalore is distracted by the war. I could definitely see the Kaggath playing out this way.