It's basically what it says. A hero should not die a stupid death, should he? Every hero should die in an epic Final Battle, not being gunned down by a tank.
If your hero's armor is successfully beaten, the hero is not counted as dead, but downed. Due to the strange bending of physiks when heroes are around, any unit with a mind can use one action to revive a hero. These heroes are back in the fight until gunned down again.
When a hero decides he wants to kill another, a duel is initiated.
-The assaulting hero declares how he wants to attack, similar to a heroic feat.
-The defender declares how he would defend from such an attack.
-Both parties roll 1d6.
-The higher roller wins. Now the defender, if alive, gets to counterattack.
-This goes on until one party has taken 3 hits.
-When one hero has taken 3 hits, he is dead. There is no way to bring him back. Put his head on a pike, and leave him to rot.
That's really all there is to it.