Friday, May 28, 2010

Sci-Fi Armour for Labyrinth Lord

Last time I talked a bit about what I’m doing with firearms, and now I’m going to talk about armour.  Moldvay/Cook/Labyrinth Lord makes armour a pretty big deal.  But descending AC limits me somewhat, and makes the math a bit harder.  So, for my sci-fi project, I’m going to bite the bullet and embrace the ascending AC. 

May Thor have mercy on my poor lost soul.  ;)

The nice thing is, this really gives me no upper limit on AC or on attack roll bonuses for weapons.  I can get really crazy if I want to.  I don’t think I want to, but I like having the option open.

The real handicap here is that this game only has one flavor of AC.  Sure, I could create all sorts of tables for impact vs. energy vs. gravitic attacks, but I really don’t want to deal with all of that.  I may change my mind later, but for now, I think I’m going to try to hew to a single sort of AC. 

Armour is fairly vague in my Labyrinth Lord games.  “Plate Mail” can mean the articulated armour of the Renaissance knight, but it can also mean the breastplate, helm, and grieves of the classical hoplite.  I’m going to be equally vague here.

Soft Armour (+5 AC): this is woven layers of special flexible, cloth-like materials.  It usually means bulky flack-jackets, but if you’re willing to pay ten times the list price you can get stuff that can be hidden under most clothing.  Most space suits count as soft armour, especially those fashioned to be used in construction, mining, or other hazardous activities.

Rigid Armour (+7 AC): fashioned from hard plates of specialized materials.  This can’t be disguised easily.  Armoured space suits are those with rigid plates attached for additional protection.  These are usually only seen on folks expecting to get shot at, though some environments are dangerous enough to warrant their general use.

Light Powered Armour (+9 AC): Powered armour gives a boost to the wearer’s strength, stability via a rigid, robotic exoskeleton while onboard sensors provide enhanced perception.  This results in an effective STR of 18 while wearing the armour. Light powered armour is used primarily for scout units and those expected to fit into small vehicles.  Still, if the power fails, it’s nearly impossible to move in.

Living Armour (+10 AC): Living armour is a biological parasite that fits itself around its wearer, who enjoys additional protection, enhanced strength and reflexes, as well as boosted senses.  The results are a +1 to STR and an increase in the wearer's hit points by 25% (rounded down). The suit's hit points are lost first, but the loss of the last hit point doesn't kill the suit or affect the wearer's AC in any way. In addition, it can never run out of power.  To get a suit of living armour to stop working, you have to kill it.  It’s the armour of choice for those who can afford it.  Unlike other armours, it needs to be fed regularly and can be extremely particular about who wears it.

Heavy Powered Armour (+11 AC): heavier version of the light powered armour.  It grants the wearer a STR of 19 while the power lasts. Generally supplied to shock and forward assault troops, as well as the spearhead of boarding parties.  If the power goes out, you can’t move.  It typically comes with its own internal life-support, making it, in effect, a really fancy, sturdy space suit, though you’ll almost never see it used anywhere besides combat.

Ulta-heavy Powered Armour (+15 AC): really more a small artillery platform than armour per se.  Movement is slow even when it’s powered up, and if the power fails you probably can’t even get out of it! The STR of the wearer is effectively 20 while the suit is operating.

Arachnid Armour (+12 AC): a heavy version of living armour, this adds four additional limbs with diamond claws for combat or climbing.  It can be used to manhandle heavy equipment or weapons, be ferocious in melee, or travel overland at great speed, even over rough terrain.  The wearer has their hit points increased by 50% (rounded down) and the effective strength of the limbs is 18. It needs to be well-fed for optimal performance, however, and it eats like a horse.

UPDATE: Added STR and hit point bonuses to some of the armours.

Photos by ellenm1 and brava_67.

Thursday, May 27, 2010

Gauss Weapons in Labyrinth Lord

Ranged combat in Moldvay/Cook still gives me fits. Yeah, it works well enough, but only being able to shoot once every ten seconds is insane, even for crossbows. Things get worse when you start looking at adding modern or futuristic firearms.

When translating firearms to D&D, most folks start with the damage. They want guns to be as dangerous as they are in real life, so turn to tools like exploding damage dice. This certainly does make firearms dangerous to high-level characters. However, that doesn't quite work with my sense of hit points being the ability and will to continue to fight, rather than structural integrity. Traditionally, fire arms were seen as the great equalizer because they rendered strength, size, expensive equipment, and, in many respects, skill, largely irrelevant. Anyone with a modicum of training and steady hands could too easily slay a knight in the finest armor, atop the most expensive horse, and with a lifetime of training. "The good Lord made all men," as the saying goes, "but it was Samuel Colt who made us equal."

So I'm thinking of approaching fire arms from the other end, and giving them bonuses in the attack roll. These bonuses are going to be pretty hefty. Even a simple firearm like a matchlock or flintlock deserves a +1 or +2. Once you're talking about shotguns and full-auto machineguns, bonuses of +5 or more may not be out of the question. (Keep in mind that the spread of a shotgun and the spray-and-pray firing technique of an assault rifle on full auto are less about putting lots of holes in your target and more about putting lots of lead in the air in order to increase the chances of hitting something.) Firearms will likely do about the same amount of damage as other weapons, since losing hit points is more about stress, distraction, and exhaustion than it is about physical integrity and blood loss.

Because a certain someone is obsessed with gauss weapons, we'll be taking a look at those here. The really cool thing about these weapons is that they allow a wide range of ammunition types. So let's see what we can do with that:

Solid Slug - the most basic projectile. This grants a +3 on the attack roll, +5 with autofire (but keep in mind that this increases the chance of hitting something else as well). It has an effective range of 1,200 feet and does 2d4 damage.

Smart Slug - this is a solid slug with wings. It can’t shoot around corners, but it is far more accurate. It can only be fired in single-shot mode, enjoys a +4 bonus on the attack roll, and an effective range of 2,400 feet. However, this projectile requires additional gear for properly selecting a target. It also does 2d4 damage.

Explosive Slug - a solid slug that goes boom. Using the same targeting gear as the smart slug, this one actually can reach round corners. When it goes off, roll a normal attack roll for every target within a 5 foot radius, adding +3 to all the attack rolls. Those hit take 1d6damage. Autofire is not an option.

Screamer Slug - a solid slug that whistles and then goes boom. The screamer slug has an effective range of only 900 feet. It doesn't require any special targeting equipment. However, it emits a hideous whistle as it flies through the air. It also explodes after it hits the target, doing 2d6 damage after a successful hit. The combined effect is a -2 on the morale rolls of anyone being shot at. However, the wonky aerodynamics give it only a +2 on the attack rolls, +3 with autofire.

Force Slug - a slug that pierces force fields. This is very expensive round generates its own force field designed to penetrate defensive force fields. It has an effective range of 900 feet, but is otherwise just like a solid slug.

Taser Slug - a slug that shocks. This acts just like a solid slug, but only does 1d6 damage and doesn't kill your target.

Needle Shell - a disintegrating shell that releases a swarm of tiny needles. The effective range on this is only 200 feet. The attack roll bonus is +4, +6 on auto fire. The needles can be used to inject a wide variety of toxins into the target. Usually, this at least doubles their cost.

Painter Shell - this shell splatters a gooey substance on the target that calls out to smart slugs. It adds an additional +2 attack bonus to Smart slugs fired at the same target. It only does one point of damage, but is otherwise just like a solid slug.

Am I missing any good ones?

Art by Ludovico Marchetti.

Monday, May 17, 2010

"...We Raise Our Horns in Remembrance."

Yeah, this very much reminds me of what gaming was like in my neighborhood in the early '80s.

Sunday, May 16, 2010

Expectations: Iron Man 2 and Robin Hood

A good woman will reload for you. A great woman will take up a knife and start slitting your enemies’ throats.

-Stephen W. Browne (I think)

Summer blockbuster season is upon us once more, and for the first time in forever, I’m in the theaters. Not on opening day, mind you, but still…

The big two so far for me have been Iron Man 2 and Robin Hood. I was going to see these no matter what the reviewers and all said, and now I have, so I’m going to toss in my two cents.

Iron Man 2 is at least as good, and more fun, than the original. Squaremans is right; it’s got just as much fun in the build-up without asking us to believe someone goes utterly crazy and stupid in the final act to set up the compulsory Battle o’ the Suits at the end. Tony Stark is equally fun and self-destructive (with arguably decent reasons this time), Pepper Potts is a sultry, grown-up Hermione Granger (no, really, think about it), and Tony’s driver/bodyguard Happy pulls off being comedic relief without being a buffoon. Think a less furry and taller Gimly from the movies. And any movie that bookends itself with AC/DC tunes is gonna go up a few notches in my estimation.

Oddysey has described Samuel Jackson’s role in this movie as informing Tony Stark that he lives in the Marvel Universe now, where the meager elements of the periodic table are fortified with the potent, supernatural elements of Science! She’s spot on, I still think casting Mr. Jackson as Nick Fury was inspired, and I hope we get to see more of him as these movies slowly lead us towards the Avengers flick.

Robin Hood is a lot more problematic for me. First, it’s not been advertised well. This is most emphatically not a Robin Hood movie. It’s entirely an origins story.

Ok, I need to explain that. You know how in Batman Begins, the first half or so of the movie is about Bruce Wayne and how he becomes Batman, but by the last act he is Batman and he’s busy doing Batman-y things? Ditto for the first Iron Man movie, where we get a sort of sneak preview of what Stark will do in the first act, when he escapes from the terrorists, and then he’s full-on into being Iron Man by the third act.

In this Robin Hood movie, our hero doesn’t become Robin Hood until the last ten minutes of the movie. Seriously. The scene from the trailers where the sheriff asks for a nail and the notice gets pinned to the tree by an arrow and the crowd bursts into laughter? That’s maybe five minutes before the credits start to roll.

Knowing that, the movie is ok. When it soars, it really soars. Russell Crowe continues to prove he’s one of our most underrated actors today. When he responds to a quip from King John with, “To an Englishman, his home is his castle,” it’s got both great comic timing and the gravitas of English Common Law being crafted by the poetic wit and common sense of the mythic English yeoman. When Mr. Crowe starts growling orders in that rich voice of his, and the soldiers immediately move to obey, we buy it. The man has enough presence that the movie hardly needs Max von Sydow to add weight to the film, though he’s great in his role, as always.

Unfortunately, the writing, while clever, doesn’t always seem to be up to the level of that exchange about homes and castles. I can’t tell if this is a problem with the writing or the budget of the movie. We only hear about how King Richard lost the hearts of his soldiers by ordering the slaughter of innocent Muslims during the crusades, but we don’t get any tortured, washed out memories haunting the dreams of our heroes. The battles seem tiny, the villages barely larger than a handful of hovels, and when Marion shows up at the final battle with the Scary Orphan Boys in tow, it’s barely a handful of scraggly individuals, not the scary feral mob they’re clearly meant to be.

Which kinda gets at the heart of what I think is the issue here. The movie is clearly filmed to be a very intimate piece. Only it’s about international politics in 13th Century Europe and the Magna Charta, one of the most mythic political documents in Western history. The 1964 “Becket” managed similar territory by mostly shooting a big political movie sprinkled with deeply personal, poignant moments. Robin Hood tries the opposite tack, by having a deeply personal movie punctuated by moments of grand politics and war. It doesn’t quite work.

Part of the reason for that is the odd nature of the intimate moments. Much revolves around Crowe’s Robin Longstride not remembering much about his father. The final revelation, dribbled out to keep us intrigued, is underwhelming as secrets go, and serves primarily as catalyst for transforming Lonstride from a pillaging mercenary into a champion for liberty. Which means he gets to give rousing speeches about the right to trial and the right to earn an honest living without us having actually seen any summary imprisonment or much in the way of people being forbidden to feed their families. In short, it’s a writer’s cheat, and it feels like it.

So we get a movie that’s constantly trying to be greater than it is, complete with an invasion of England by France involving 13th century versions of the D-Day landing craft and grand plots and counter-plots, and yet the movie makes it feel like you can ride across the length and breadth of England in an afternoon. Marion spends most of the movie with her sleeves rolled up, being a sort of medieval Rosy the Riveter, but when she dons armour and goes to avenge the death of her father-in-law, she only manages to bring that scraggly handful of lost boys with her, and spends a good part of the mano-y-mano fight thrashing and sputtering in the surf. Sure, I know Robin’s got to slay the baddie at the end with an arrow, but again, it feels like we’re not quite given the payoff her character promised in the beginning. (Say what you will about Tolkien being sexist, but when Eowyn squares off against the Witchking to avenge the death of Theoden, it’s Eowyn herself who slays her foe, with only a bit of help from the doughty Merry.)

Which stands in stark (pun not intended) contrast to Gwyneth Paltrow’s Pepper Potts. Not only does she run Stark Enterprises while Tony is self-destructing in slow motion or throwing together a quick particle collider in his basement, she takes control at the end of the movie, not by donning a suit of super armour and smashing people through walls, but by using the skills and resources she’s been demonstrating through the whole film to minimize the damage and take down half the villainous duo in a way that’s clean, efficient, and inside the system. Sure, fanboys will rave about Johansson’s Black Widow, but it’s Pepper who has Tony’s back through thick and thin, who keeps the lights on at swanky Stark Manor, and puts out the fires started by the villains and Tony.

All in all, Iron Man 2 gets a big thumbs-up for me, Robin Hood gets a half-hearted thumbs-up, and that’s not a bad way at all to start the summer.

Monday, May 10, 2010

What's Common?

Riffing on Oddysey’s latest posts, but going the other way, part of my world design process is deciding just what the language “Common” is. It’s a handy device to make sure everyone can talk to each other, but it also implies something about the setting. The Common tongue grows out of power; everyone speaks it because it was the native tongue of those with some sort of authority. That power could be political, but it could also be commercial, cultural, or religious.

In history, there have been a handful of common tongues. Latin, of course, is the one most folks think of. Not only was it the language of Rome and her empire, but it was bequeathed to the Catholic Church that followed. Most didn’t speak it well in the Middle Ages. It’s common to come across documents written with Latin words but local grammar, which makes understanding a real mess. And the closer you get to the Renaissance, the fewer outside the church who speak it.

A few hundred years after the Renaissance, the rise of France’s cultural power made French the lingua franca of diplomacy and culture. But in the world of the burgeoning science of geometry, the lingua franca was Greek, because so much of the work being done was based on an ancient Greek foundation.

Today, the closest thing the world has to a Common tongue is American English. While the vast American entertainment-industrial complex is primarily responsible, the fact that English is the native language of the ‘net certainly doesn’t hurt.
So we’ve got lots of models to work from when thinking about where Common comes from in a campaign. It can be the language of a great empire, either past or present, of some international organization like a church, or the language of scholars or popular culture. Which it is will define something of your campaign.

Traditionally, the Common tongue has been the language of a fallen empire in my campaigns. That fall wasn’t too long ago; everybody has family history of the days back when the empire still stood, though for short-lived humans that may have been great-great grandfather’s day. In my current Doom & Tea Parties game, Common is the language of the Second Lizardfolk Empire, still standing but also clearly on its last legs. In both cases, the collapse of empire gives the world a Points of Light feel. Pockets of civilization remain, but between them can be seen the unraveling of culture, law, and safety for the common folk, with lots of opportunities for brave (or unscrupulous) adventurers.

In a previous campaign, the Common tongue was a trade pidgin of Gnomish. The gnomes, being great traders who occupied a hilly land near the center of the continent, went everywhere and traded with everywhere. With the gnomes and their trade comes news of far-off lands and connection to them as well. The rampages of a dragon in far-off Gebelstor meant imports of iron would become rare, raising the price. Elven raids along the coast of Berian, breadbasket of the continent, might lead to hunger and malnutrition throughout the lands. There’s no end of adventure hooks for our heroes to chase as the gnomes bring word of great happenings from the icy wastes of the far north to the tropical Emerald Coast. Everything feels connected, and where that connection is mostly felt by its absence with the fallen empire, in the a campaign strung together by trade every action the PCs have can be seen to reverberate through the economic web of
the gnomes.

UPDATE: How this actually works in the real world: English becomes Globish.

Art by Jean-Leon Gerome and Hermann Meyerheim.

Saturday, May 08, 2010

Review: Gratuitous Space Battles

It says something about my computer game playing habits lately that I had to look up "tower defense game." It doesn't surprise me that people find these sorts of games fun. Tower defense was basically my primary strategy when playing RTSes, especially of World of Warcraft II. That said, RTS is not my genre of choice these days. Most of my gaming is older turn-based strategy, like Master of Orion II, Bio-Ware RPGs, and neat little things like Positech Games’ Gratuitous Space Battles.

The game is exactly what it says on the tin: really pretty (even though sprite-based) battles in space between slow crawling capital ships and swift little fighters. The backgrounds are full of the Technicolor glowing nebulae that the Hubble space telescope and Babylon 5 have made us come to expect in space. What's a little odd is the focus of the game. It's not a flight sim with RPG elements, like Elite, or 4X game like Master of Orion. It's not even a turn-based RTS combat simulator like Starfleet Command. Instead, it really is more like a tower defense game, except your towers are spaceships which crawl slowly across the screen towards enemy spaceships which are crawling slowly the other way toward your ships. You don't command ships in the battle; instead, you set things up beforehand, unleash the fleets and sit back to watch how it turns out.

So what do you do? The first stage of the game is designing your ships. The game comes with four races, three of which you have to unlock through successful gameplay. Each class has different hulls in three categories of ship: small zippy fighters, not quite so small and not nearly as zippy frigates, and big lumbering cruisers. Each hull has a certain number of hard points and slots for general equipment. In the ship creation screen, you fill the hard points and equipment slots with the gear you want your ship to have. If you need a fighter-killer, you outfit your ship with quick, low-damage canons and missiles, while another ship may be equipped with big but slow beam weapons that pack a lot of punch. Most hulls add extra bonuses towards certain stats on the ship like power generation or speed.

After you've designed your ships, it time to see how they actually perform in combat. The game comes with some preset scenarios. When you load one of these up it first tells you about any special conditions. These can range from the classic Wrath of Khan nebula situation where shields don't work, to logistical limitations on which pieces of equipment or hull types can be used. You are then shown a map of the territory in which the combat will take place. Maps vary in size, so small little skirmishes don't necessarily have to start with your ships crawling diagonally across a vast expanse towards the enemy for hours before the fighting actually starts. You'll see the enemy fleet already in its line of battle. This allows you to arrange your fleet in tactical response. Usually, this will probably mean some variation on the denied flank, but since you can run any scenario as often as you like, you can try out all sorts of different configurations and combinations of ships.

As you're arranging your ships, you can give them commands that they will carry out once the battle starts. These consist of which ships to engage in combat at which distances, formation and escort commands, and whether or not to attempt to withdraw from the front lines when they start taking too much damage. As with most computer-based tactical AI, the actions of your ships can be both predictable and, at times, really wonky. This does allow you to achieve certain effects in a roundabout sort of way. For instance, if you don't want your fighters to speed ahead straight for the enemy, you can assign them to escort a fragile frigate with paper-thin armor. The fighters will then swirl around the frigate as it crawls towards the enemy, and then swarm over the enemy once they've destroyed the frigate.

After you've got your fleet arranged, you click the “fight” button and watch them go. The space battles are gratuitously gorgeous, as you'd expect. Great glowing missiles leave trails in their wake, glittering bolts of plasma glitter across the screen, and laser beams rake their targets, all causing explosions and fires to erupt on the targeted hulls. Unlike other games on similar subjects I've seen, Gratuitous Space Battles actually shows you the damage being done to enemy ships. In spite of the sprite-based graphics, you can zoom in and watch the turrets on the ships turning towards the enemy and firing. You can also see them burst into flames when they are crushed by missiles and laser beams. Hulls become peppered with flaming holes that belch smoke and sparks. Destroyed ships drift as blackened and shattered hulks, bits of twisted metal floating as debris in your battle space. The whole thing is just fun to watch.

After the battle you can review reports on which ships and weapons did (or suffered) the most damage. These reports are not quite as detailed as I would like, and they don't tell you which of your ships hurt any particular ships on the other side. Or at least, I haven't been able to figure that out in the data I've seen. Still, it's pretty easy to figure out which of your weapons are effectively harming the enemy and which are just pinging ineffectively off their shields.

And that's the game. Rinse and repeat as desired. You can set up a situation and fleet and challenge others to take it on, or accept challenges others have created. It's quick, easy to get into, and fun to play. It doesn't require a whole lot of time, and if the space battles are crawling on a little too slowly, you can always speed up the action. The music is appropriately strident, full of drums and horns, but I imagine it's going to get old very quickly. Still, the music and eye-candy are surprisingly good for a game that sells for only US $10. If you do get bored with the fleets provided by the basic game, a few modded fleets (some based on IPs like Star Wars and Starship Yamamoto, a.k.a. Star Blazers) are available, as are official add-ons of new fleets to fight with or against. At the price, it's hard to argue with. But there's no substitute for downloading the free demo and trying it for yourself.

Wednesday, May 05, 2010

Red vs. Green: Taking the House Rules for a Spin

Because scottsz asked for it, and I have a new player joining our game, here's an example of what combat looks like with my house rules.  Keeping things simple, I'm going to use two 5th-level fighters.  Since I have a red d20 and a green d20, our battle will pit the Green Knight against the Red Knight.  The Green Knight has a Dexterity of 15 and the Constitution of 13.  The Red Knight has a Strength of 13.  The Green Knight has 21 hit points and the Red has 28.  Both wear chain mail and a helm.  The Green Knight wields a sword and shield; the Red Knight wants this over quick and hefts a battle ax.

As the two approach each other, we encounter the first house rule: initiative.  The battle ax has an initiative of 8 as does the sword.  However, the Green Knight's Dexterity gives him an initiative adjustments of +1 so he goes first.  The Red Knight’s armor class is 5; the Green Knight needs to roll 12 or higher to hurt him.  Unfortunately, he rolls a 3.  The Green Knight's AC is 4 thanks to shield.  The Red Knight needs to roll a 13 or better.  He rolls an 18!

Because the battle ax is a two handed weapon, it does 2d4 damage.  The Red Knight rolls very well and does the max possible: 9 points.

Pressed hard by the Red Knight's aggressive opening, the Green Knight attempts to rally.  He succeeds with a roll of 19.  The one-handed sword does 1D6 damage; the Green Knight rolls a 1.  The Green Knight’s rally has stolen the Red Knight’s momentum; the Red Knight rolls an 11.

The next round sees our two combatants exchanging blows to no real effect.  The Red Knight, however, remains undaunted and rolls a 15.  He rolls a 4 and a 1 for a total of 6 (4+1+1 for STR) damage thanks to his high-strength.  The Green Knight is clearly struggling.  Another blow like that could take them out of the fight.

He's not down yet, however.  In the next round he rolls a 13.  The roll for damage is a 5.  The Green Knight is growing desperate and his fancy sword-work is simply being power through by the stronger Red Knight.  The two knights continue their clash, with the Green Knight wearing away another two of the Red Knight’s hit points.  The Red Knight barely seems to notice and lands another telling blow on the Green Knight.

With only six hit points remaining, the Green Knight knows he's in trouble.  In a desperate bid for survival, the Green Knight throws shield up between his fragile body and the Red Knight's cruel ax.  The heavy blade shatters wood and steel, but the Green Knight emerges still on his feet.  His left arm is bruised but not broken.  He draws his dagger with his left hand as a companion for his sword.

The Green Knight still rolls only one die for his attacks and his next roll is a 14.  For damage, he rolls a 3 and a 1.  Since he's using two weapons he chooses the best of those rolls; so the Red Knight takes three points of damage.

Both knights are now feeling the strain of the combat.  They circle one another warily, testing each other with feints and sudden attacks.  The Green Knight breaks through first and drives his foe back, dealing four points of damage.  He presses his momentary advantage, doing another three points of damage.  But the Red Knight is having none of it.  He shrugs off the Green Knight’s attacks, and lets his foe walk straight into his ax for another four points of damage.  The Green Knight unleashes a furious rain of blows, doing six points of damage and reducing the Red Knight to just four points.  But the Green Knight has only two hit points, and the Red Knight’s response does seven points of damage.

That reduces the Green Knight zero hit points.  He must now roll on the Table of Death & Dismemberment.  The 2d6 turns up 7: knocked out for 2d6 rounds, unless wearing a helm.  Luckily for the Green Knight, he is wearing a helm and is only stunned for one round.  Even luckier, the Red Knight is so shocked by his success that he fails to follow up on it by rolling a 3.

The Green Knight recovers from his stupor and swings at the Red Knight.  He rolls a19, and then a 1 and a 5 for damage!  That brings the Red Knight to zero hit points, and he rolls a 9 on the Table of Death & Dismemberment.  As he's also wearing helm, the ringing blow to his noggin only knocks him down.  He forgoes his next attack to get back on his feet; otherwise, he'd be at -2 to attack and the Green Knight would be a +2 to attack.

But no sooner has the Red Knight regained his feet but the Green Knight thwacks him again!  There is no need to roll for damage; the Red Knight can never have fewer than zero hit points.  So we go straight to the Table of Death & Dismemberment.  The roll is a 3: fatal wound.  Die in 1d6 turns.

The Red Knight is in no shape to continue the struggle.  Under some circumstances, I might let a PC fight on if there is a compelling reason to believe they would struggle on in spite of this grievous wound.  The Red Knight, however, is done for.  The Green Knight takes mercy on his foe and uses his dagger to provide a coup de grace, ending his agony.

Art by Frank William Warwick Topham and Gustave Courbet.