As has been noted elsewhere, at some of its most dramatic moments, the professor's curious mix of tale-telling and game can involve combats, about which the professor is remarkably clear-eyed.
Such encounters, be they skirmishes or pitched battles, arise from the scenario and choices made in play: they are never forced for their own sake, and the players' characters often (but not always) have a chance to avoid them. Rarely, if ever, do two equally matched opponents stand forth for a gentlemanly bout.
Sometimes, whatever playing pieces are at hand, from chess-men to checkers, may be first arranged to show the rough situation, but this is far from necessary, and short encounters may well be resolved without them.
Whoever chooses to act and move first, whatever the consequences, does so. If the characters are ambushed, then they must respond to the ambush. If they charge or strike, then they have the initiative. From then on, each move and counter-move is resolved as most makes sense. Every player may take some sort of action before the turn is ended.
Given the risk, dice are rolled to resolve each combat. Each player rolls, and the professor adjudicates the outcome based on their skills, tactics, armaments, and position. Usually, a roll of six or more is required for the character to hold their ground and at least keep up their guard. Depending on the foe, a higher roll may be required to strike and prevail. For example, we see in the notes that a "man-at-arms" or "greater goblin" may be slain with a roll of seven or more, but a fearsome troll is wounded only on a roll of nine or more, and a dragon struck on a twelve only. More formidable foes may withstand several hits before they are felled. Even so, when allocating hits, the higher the roll, the better.
A roll of less than 6 means that some sort of setback, a blow, hurt, or wound, is suffered. The lower the roll, the more severe the consequence. The professor is unsparing of both sides, and so a player who rolls low may be wounded, dazed, or even felled and left-for-dead. Some enemies wield dreadful weapons, which may leave a festering wound or even sickness of spirit.
Players look always for sixes – the "crown" on the dice they roll, and two crowns are unstoppable. A single crown indicates a minor boon or advantage. Perhaps the blade bites deep, hampering the foe, or an opponent can be daunted or forced to retreat. Ones, the "evil eye" are feared. A single one may show a disadvantage or complication, but double-ones indicate an evil turn. When ones and sixes appear at the same time, the roll is an alarming close call, with gains and losses for both sides!
Fights do not necessarily end in death. Stern opposition may indeed cause the enemy to falter, but they may flee, or regroup, or attempt to surround the adventurers or even split them. Many goblins could retreat from a single warrior, only to turn and launch arrows at his shield to weight it down. By this token, wise warriors know when to flee, and when a threat is beyond their powers. Recklessness and blood-lust are not rewarded in the Green Dragon game.
Against the most dreadful monsters, only a cunning strategy, knowing the fatal flaw in a dragon's hide or the means to pierce the spell that protects an ancient horror, has any real chance of succeeding. There is always a place for heroism, though, and even a common soldier may hope to defeat the old and strong and cruel if he or she is stout-hearted and battle-wise.