Up to D&D
This comes from “Questions most frequently asked about Dungeons & Dragons rules” from The Strategic Review Vol. 1, No. 2, Summer 1975
Combat Example:
10 ORCS surprise a lone Hero wandering lost in the dungeons, but the die check reveals they are 30’ distant at the time of surprise, so they use their iniative to close to melee distance. lnitiative is now checked. The Hero scores a 3, plus 1 for his high dexterity, so it is counted 4. The Orcs score 6, and even a minus 1 for their lack of dexterity (optional) still allows them first attack. As they outnumber their opponent so heavily it is likely that they will try to overpower him rather than kill, so each hit they score will be counted as attempts to grapple the Hero:
Assumed armor of the Hero: Chainmail & Shield — AC 4.
Score required to hit AC 4 — 15 (by monsters with 1 hit die).
Only 5 Orcs can attack, as they haven’t had time to surround.
Assume the following dice scores for the Orcs attacks: Orc #1 - 06; #2 - 10; #3 - 18; #4 - 20; #5 - 03.
Two of the Orcs have grappled the Hero, and if his score with 4 dice is less than their score with 2 dice he has been pinned helplessly. If it is a tie they are struggling, with the Hero still on his feet, but he will be unable to defend himself with his weapon. If the Hero scores higher than the Orcs use the positive difference to throw off his attackers, i.e. the Hero scores 15 and the Orcs scored but 8, so the Hero has tossed both aside, stunning them for 7 turns between them.
Round 2: lniative goes to the Hero.
Score required to hit Orcs — 11 (4th level fighter vs. AC 6).
Assume the following dice score by the Hero. Note that he is allowed one attack for each of his combat levels as the ratio of one Orc vs. the Hero is 1:4, so this is treated as normal (non-fantastic) melee, as is any combat where the score of one side is a base 1 hit die or less.
Hero: 19; 01; 16; 09. Two out of four blows struck. There are 8 orcs which can be possibly hit. An 8-sided die is rolled to determine which have been struck. Assume a 3 and an 8 are rolled. Orcs #3 and #8 are diced for to determine their hit points, and they have 3 and 4 points respectively. Orc #3 takes 6 damage points and is killed. Orc #8 takes 1 damage point and is able to fight.
Continued attempts to overpower the Hero are assumed, and no less than 4 Orcs are able to attack the Hero from positions where his shield cannot be brought into play, so his AC is there considered 5, and those Orcs which attack from behind add +2 to their hit dice. In the case it is quite likely that the Orcs will capture the Hero.