Nick Hendriks

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Mutant Grinder, or 1d20 Down The Line

The year 2005: a grim future dystopia where the wealthy live a life of indulgence on the surface and everyone else tries to survive in The Ruts. In this industrial hell heavy metals poison the ground, radiation poisons the water, and disease poisons the air. Down in The Ruts nobody's body works right anymore. Babies can't be conceived the old fashioned way (not that it stops anyone from trying), so cloning pods called "Tube Mamas" convert bio-waste into new humans, more or less. You're one of these poor bastards.


Table of Contents


In a Nutshell

If you are familiar with common d20 systems, this one will look pretty similar. Here are the key elements to this system for veterans who want to jump right in without reading everything:


Mechanics

Resolution Mechanic

To overcome an obstacle, roll 1d20 and add the appropriate stat. If it meets or beats the difficulty value of what you're trying to do, you succeed. This procedure is called a "check."
Some abilities or circumstances will impose bonuses or penalties to checks. Just add that number to your total before comparing it to the difficulty value.
If you are competing with another character both of you roll 1d20 and add the appropriate stat. Whoever gets the higher result wins.

Difficulty Guidelines

Some benchmarks for how hard things are:

Bonus and Penalty Guidelines

Life and Death

You start the game with some hit points. If you lose all your hit points you die!
Each hour spent resting regains a number of hit points equal to your level (plus an additional hit point if you eat during the hour) up to your maximum.

Inventory

You can carry a number of items equal to your STR. Stuff worn on your body or carried in your hands counts towards this number. Identical small things (like ammunition, rations, etc.) can be stacked up to 20 in a slot. Wee little stuff can just go in your pockets (if you could close your hand around it, it probably counts as little stuff). Exercise reason here.
If all of your inventory slots are full your base movement speed drops a category. If somehow you wind up carrying more than you have slots for you are unable to move or attack until you ditch some stuff.

Weapons and Armour

Armour: Wearing armour helps to protect you from damage (duh) by increasing your Armour stat. There are two categories of armour:

Weapons: Weapons help you to do violence. Basic weapons have a couple of properties:

Weight:

Range:

Common Weapon Examples:

Special Weapon Examples:

Unarmed Combat and Improvised Weapons
If you want to just clobber someone with your bare hands you can make a Strength check, dealing 1d4 damage on a hit.
Improvised weapons always use Strength if you're swinging them and Dexterity if you're throwing them, and always deal 1d4 damage on a hit.

Explosives

Explosives use special rules. An explosive can target up to 3 targets close by to each other. The targets makes a contested Dexterity check against the attacker, taking the explosive's damage if they lose. Explosives typically do 1d20 damage.

Combat

This works like every other d20 game, so if you're familiar with those, just use the rules you're familiar with. Otherwise, read on.

Initiative

When combat breaks out everyone rolls initiative (as a Dexterity check) and takes a turn in descending order. Just keep using this order as long as combat is ongoing, cycling back to the top of the order once everyone has gone.

Your Turn

On your turn you can take one action and move. You can do these in any order, and you can divide up your movement up, taking a portion of it before your action and a portion after.

Actions

Most things you might think of doing in combat are actions. Making an attack is a classic example, but something like fiddling with a computer might be an action. Trying to bust down a door is an action. Digging something out of your pack is an action. Pretty much anything that'll take you more than a second to do is an action.
Some things aren't considered actions and can be done for free. Flipping a light switch is free. Talking is free. Dropping something is free. Picking something up off the ground is probably free if it's nearby, unobstructed, and isn't especially heavy. Again, exercise good judgement here.

Attacking

When you attack, make a check using the skill associated with your weapon (plus any bonuses) where the difficulty is the target's Armour. If successful roll the weapon's damage die.

Critical Success and Failure

Critical successes and critical failures only occur when making attack checks.
A roll of a 20 on the d20 die is a critical success. You successfully hit the target no matter what and get twice the maximum damage on your damage die (weapon that deals 2d4 damage deals 16 damage on a critical success).
A roll of 1 on the d20 die is a critical failure. You miss no matter what and deal no damage, plus your weapon is Busted and does not work until you get it repaired by someone who knows how. Some Mutations trigger on critical successes or failures. These occur on top of the normal critical effect.

Movement

You can move on your turn. Unless something on your character sheet says otherwise, your base movement speed is Medium. That's a brisk walking speed, just enough to put a little sweat on your brow if you keep it up for a while. Slow is a saunter. Fast is a sprint. If you move at any speed slower than your base speed, you are considered to be moving carefully and may get a bonus to checks in certain circumstances. Moving faster than your base walking speed may incur penalties to checks in certain circumstances.


Character creation


Mutations

  1. Time Manipulator: You move through time at a different rate than other people. You get an extra action every turn.
  2. Chameleon Hide: You are able to turn nearly invisible. It takes a lot of concentration and takes an action to activate.
  3. Gene Collector: You have a weird mosquito mouth. As an action you can harvest the genes of a recently deceased mutant to gain their mutation.
  4. Handy: You have two extra arms.
  5. Headcase: Your enormous skull makes you look like a grotesque bobblehead doll, but it protects you from psychic attacks, and you are immune to being stunned.
  6. Stinger: When you roll a critical hit on a melee attack, the target takes an additional 1d6 poison damage and is stunned for a turn.
  7. ESP: As an action you can see a hazy image in your mind of all living creatures within 10m. You can see what they're doing and their immediate surroundings within 1m, but you can't determine their distance or direction from you.
  8. Rapid Decomposer: Your gut biome is enthusiastic. As an action you can blorp out some of it onto a dead body, which begins to bubble and smoke and will explode violently at the end of your next turn, dealing 1d20 damage to anyone nearby.
  9. Fiery (good): Whenever you roll a critical failure you can belch flames at the target of your attack, setting them ablaze. They take 1 damage per turn until they do something to extinguish the flames.
  10. Killer Instinct: Your hands constantly flex and relax, and your eyes always have that look in them. You get critical hits on d20 rolls of 18, 19, or 20.
  11. Gassy: You can release a 5m cloud of noxious green gas. It lasts for 1d6 turns or until a strong wind disperses it. Creatures (other than yourself) who start their turn in the cloud or move into the cloud take 1 poison damage. Any open flame within the cloud (including gunfire) causes it to ignite, causing 1d20 damage to all creatures inside. You cannot produce more gas until you have eaten while resting for an hour.
  12. Wings: A bug got mixed into your Tube Mama, so now you've got wings. They're not great; you can't gain any height with them, but you can glide a bit and don't take fall damage.
  13. Lizard Limbs: Whenever you are grappled or otherwise stuck, you can drop a limb to escape. One limb lost this way regrows after a 1 hour rest. If you're missing more than one limb you can choose the order in which they grow back. Regrown limbs are red and shiny for 24 hours.
  14. Mr Knife Guy: Every time you roll a critical hit a 10" blade pops out of your body somewhere, which you can leave attached, or snap off with no harm to yourself. You decide where it comes out each time. It's made of some kind of neon-pink crystal.
  15. Bloody Generous: So long as you are within touching distance you can donate your own hit points to any target through thin red tentacles which protrude from your torso.
  16. Rat Pilot: Your body is actually piloted by a rat. The rat can exit your body and do stuff while your body stands dormant. It has the same stats as you except it has 1 Strength, 1 HP, and gets a +5 bonus to Dexterity. If your body dies the rat can abandon it and continue on without it. You are also inexplicably pretty good at cooking.
  17. Fleet of Feet: Your legs ends in a writhing mass of tiny feet. You can flow over difficult terrain as long as you're barefoot.
  18. Gulper: You can carry more than would normally be possible by swallowing it. Every item you swallow gives you a -1 penalty to Dexterity. You cannot carry more items if it would reduce your Dexterity below 1. To retrieve the items you must regurgitate them all at once.
  19. Airbags: Whenever you take combat damage, big fleshy sacs inflate from your body. Your armour rating raises by 1, and your dexterity decreases by 1. The sacs will fall off after 1 minute. If five or more sacs are simultaneously deployed you begin to suffocate, taking 1 damage per round.
  20. Gills: You can breathe underwater.
  21. Divisible: You are lumpy and look like you're made of putty. You can separate your body into two miniature versions of yourself, each half your size. They each get half your maximum and current hit points (distributing any uneven remainders as you prefer). One half gets a -10 penalty to each STR, CON, and DEX (to a minimum of 1). The other half gets a -10 penalty to INT, WIS, and CHA (to a minimum of 1). The two halves act independently, and must distribute carried gear between them (bearing in mind their carrying capacity). If one half dies, both die. The two halves can rejoin as long as they can touch.
  22. Exploding Teeth: You can pull out your teeth and throw them at a target as a ranged attack, dealing 1d20 damage on a hit. However, you start life with 2d6 teeth and they never grow back.
  23. Golden Goose: At the start of each day you produce a lump of ambergris worth 1d20 bucks. It comes out the bottom.
  24. Pipes: Your Tube Mama got some junk in it, and now you have a bunch of mechanical bits embedded in you. You can sacrifice 1HP to repair a mechanical thing.
  25. Trash Compactor: You can eat anything soft enough to chew. If it's not really food, you have to sleep for an hour to digest it and gain the benefits of eating.
  26. Pied Piper: You can take control of a small animal you can see and control it (your body stays still). If the animal dies while you're controlling it you take 1 psychic damage and your Intelligence permanently drops by 1.
  27. Extendable Neck: Your neck can extend, doubling your normal height.
  28. Eye Guy: Your head is riddled with extra eyeballs. Get a +5 bonus to rolls involving sight and to ranged attacks, but when you roll a critical failure you become overstimulated, taking -5 to all checks until the end of your next turn.
  29. Sixth sense: You can psychically detect small objects that are in groups of six.
  30. Fight or Flight: When you roll a critical failure, animal instinct takes over. Roll any die. If the result is even you immediately make an additional attack against the creature nearest to you (if you're holding a weapon, you use it for this attack). If the result is odd you immediately run your maximum speed (regardless of any movement you've done this turn already) to distance yourself from as many enemies as possible.
  31. Magnetic: You get a +5 bonus to any roll involving grabbing metal objects, whether that's to steal them, prevent them from being stolen from you, etc. Unfortunately you also take a -5 penalty to AC when you're being shot by bullets or any other metal weapons.
  32. Alpha: All animals become wildly agitated when you get within 10m, making an enormous racket and trying to flee your presence.
  33. Mind Over Matter: As an action you can reduce one of either STR, CON, or DEX by 1 and increase one of either INT, WIS, or CHA by 1. Your body gets all withered, and your head grows larger. This change is permanent.
  34. Astral Bloodhound: You can astral-project your sense of smell within 1km.
  35. Carnivore: If you eat meat when you rest you gain an additional hit point beyond the normal allotment. If you don't eat meat you do not gain any hit points at all from rest or other food.
  36. Snail Trail: You constantly produce loads of mucous which you leave in a trail behind you. Creatures can move through it safely if they move below their base speed, but slip and fall if they move through it at their base speed or higher.
  37. Crackly: Every joint in your body cracks and snaps when you flex it. You ALWAYS fail stealth rolls if noise is a factor.
  38. Incandescent: Your body can glow on command. You can choose to emit light from your body. When you do, roll 1d6 to determine the brightness of the light:** 1-2:** Dim light. 3-4:** Bright light. 5-6:** Blinding white phosphorous (everyone nearby within line of sight takes a -5 penalty to all rolls requiring vision). The brightness cannot be changed until you rest for an hour, at which point the light goes out and you can use the power again.
  39. Psychic Blast: As an action you can release a blast of psychic energy which deals 1d6 psychic damage to up to 3 targets within 10m. You immediately fall unconscious for 1 hour.
  40. Birdlike: Your base movement speed is Fast. You take 1 extra damage from physical sources.
  41. Fling: Your legs looks like they came off of a grasshopper. You can choose to do a big leap. Make a difficulty 20 Dexterity check. If you succeed, you jump up to 50m in any direction you choose. If you fail, you fly 1d20m in a direction determined by a d6 and land on your back: 1: North, 2: East, 3: South, 4: West, 5+: Directly up (fall damage applies).
  42. Incorporation: Any item in your possession while you are resting becomes fused to your body. You can still use it normally, but dropping it deals 1 physical damage to you.
  43. Remote Viewing: You can pull out your eyeballs and still see through them (no distance limit). You have to put it back in your head after 1 hour or it'll dry up and be destroyed. However, whenever you pull one out there's a 1-in-6 chance you accidentally smush it, destroying it forever.
  44. Mole-Eyed: You are most comfortable in the darkest places of The Rut and can see in pitch blackness. You take a -1 penalty to checks in dim light, and a -5 penalty to checks in bright light.
  45. Quadruped: Your chassis is built lower to the ground. You cannot stand upright and move on the same turn. When on all fours you cannot use two-handed items.
  46. Butterfingers: Your body secretes a slick grease at all times. When you roll a critical failure, you drop everything you're carrying. You smell a bit like popcorn.
  47. Jellybones: You always fall down when you are hit by an attack. You can squeeze through much smaller spaces than most people.
  48. Pinocchio Hands: When you roll a critical failure your fingers begin growing continuously. Every round your fingers grow 1" longer. You take a cumulative -1 penalty to attack rolls until you spend an action lopping your fingers off at their regular size (deals no damage, but does require a blade or something). They stop growing in this way after you rest for an hour.
  49. Steely Gaze: Your eyeballs have a bunch of magnetic metal crud floating inside them. You can always tell which direction is north because you can see a big red blotch in that direction. Unfortunately this means you can't see anything to the North. Strongly magnetic things can change the direction of the blotch.
  50. Prone to Vapours: When you roll a critical failure roll 1d6. That stat drops to 1 for the next hour. (Stat order:** STR,CON,DEX,INT,WIS,CHA)
  51. Lead Poisoning: Touching lead makes you sick. Lose 1HP at the start of every turn if you have any bullets (or lead of any kind) on your person, whether it's in your hand, in your gun, or in your pack. Being shot by a bullet is really bad - you'll have to dig it out or suffer this effect.
  52. Fiery (bad): Whenever you are hit by an attack you become incensed. At the end of your next turn, if you haven't successfully damaged someone (anyone), you burst into flames and take 1 damage per turn until you do something to extinguish them.
  53. Caustic Touch: Every time you rest one item in your possession is destroyed (determined randomly somehow, you figure it out).
  54. Blood Hose: Your flaky, paper-thin skin is prone to bleeding. Any time you take physical damage you lose an additional hit point, and everyone within 1m of you is blinded for a turn by a spray of blood.
  55. Dense: Your body is loaded down with heavy metals which cause you to move extremely slowly. Your movement speed is always Slow.
  56. Vector: You're sick, son, and you look it, too. You can only regain one hit point a day through food or rest. Furthermore, anyone who rests within 10m of you must make a difficulty 15 Constitution check or gain this trait.
  57. Evil Arm: You have an extra arm with a mind of its own. When you roll a critical failure the arm tries to punch someone nearby, always preferring the weakest, most vulnerable target, and never targeting your enemies. If no other friendly target exists, it attacks you. It will absolutely steal 1-handed weapons from your inventory and use them if it can.
  58. Maximum Volatility: When you roll a critical failure (a roll of 1 on a d20 die) you explode, dealing 1d20 damage to everyone in the scene. This kills you.

Classes

Pick a class when you make your character. Each class tracks a unique resource, gains special abilities, and can unlock new abilities by achieving certain objectives.

Runner

The Ruts are full of dead ends, pitfalls, and hidey holes. You'll never know them all but you know more than most.

Rove: Runners have a unique resource called Rove. They begin every day with Rove equal to their Wisdom score. Rove can be spent on certain abilities.

Gear Packs (choose one):

Level 1
At level 1 you get the following:

At the end of each day if you have completed its unlock achievement you can choose one of the following abilities and gain a level:


Greaser

The word "surplus" doesn't exist in The Ruts. Trash is treasure, and you won't let any of it go to waste.

Scrap: Greasers use a unique resource called Scrap. Scrap doesn't take up inventory space for Greasers.

Gear Packs (choose one):

Level 1
At level 1 you get the following:

At the end of each day if you have completed its unlock achievement you can choose one of the following abilities and gain a level:


Knuckle

Some folks scheme and connive, coming up with fancy ways to deal with their problems. You know the simplest method is best: go straight through and make the problem get out of your way.

Grit: Knuckles use a unique resource called Grit. Resting for 1 hour restores their Grit to equal their Constitution score.

Gear Packs (choose one):

Level 1
At level 1 you get the following:

At the end of each day if you have completed its unlock achievement you can choose one of the following abilities and gain a level:


Bookie

Street smarts are just a fact of life down in the Ruts, but book smarts are harder to come by. So are books, come to think of it.

Lore: Bookies use a unique resource called Lore. You start the game with Lore equal to your Intelligence. You can spend an hour reading a book, consulting a computer, or conversing with a willing NPC when the sum of your Intelligence scores equal 25 or higher to gain 1d6 Lore. If you roll a 1 in this way you have depleted that source of knowledge and cannot gain Lore from it again.

Gear Packs (choose one):

Level 1
At level 1 you get the following:

At the end of each day if you have completed its unlock achievement you can choose one of the following abilities and gain a level:


Holler

A panicked rabble is dangerous. An organized squad is even more so, which is why you keep your crew in line.

Clout: Hollers use a unique resource called Clout. You begin each day with Clout equal to your Charisma. Whenever an enemy makes an unsuccessful attack roll against you or an ally you gain 1 Clout. Whenever you or an ally makes an unsuccessful attack roll against an enemy you lose one Clout.

Gear Packs (choose one):

Level 1
At level 1 you get the following:

At the end of each day if you have completed its unlock achievement you can choose one of the following abilities and gain a level:

Flair

Begin the game with three pieces of flair. Choose or roll a d66 (roll 2d6 but use them like percentile dice).

11 Wraparound Iridescent Mirrorshades
12 A bandana with a Maneki-neko cat pattern
13 Big gold disc earrings
14 Bluetooth earpiece (doesn't work)
15 N95 mask
16 Indigo blue lipstick
21 Rhinestone belt
22 Cheap imitation kimono
23 Bowtie
24 Bandolier
25 A nametag from a big-box store
26 Mardi Gras necklace
31 Fishnet leggings
32 Kneepads
33 Wallet chain
34 Fanny pack (teal and cyan)
35 Jock strap / cup
36 Jorts
41 Knee socks
42 Rollerblades
43 Flip-flops
44 Stilettos
45 Steel-toed boots
46 Wooden clogs
51 Wrist sweatbands
52 Plastic decoder ring
53 Fingerless winter gloves
54 Casio watch
55 Stick-on nails
56 Elbow pads
61 Fox tail
62 An iron-on patch that says "Expletive Assistant"
63 Chrome fangs
64 Police hat
65 Propellor beanie
66 Fake muscle suit

Gamemaster Section

Shopping

It's your call what kind of stuff is available for purchase in your game, but the Ruts are meant to be grim, so the few merchants they encounter probably won't carry everything on the following list.

Prices

Prices listed are in Bucks.

Gear
1 - 5 Rations
1 - Bandage
1 - Handful of smokes
1 - Chalk stick
1 - Lockpicks
1 - Multitool
2 - Megaphone
2 - 20m Rope/Chain/Hose
2 - Booze
2 - Microscope
3 - Book
Armour
1 - Fancy / Special Clothes
2 - Light Armour
3 - Heavy Armour
Weapons
1 - Light Melee
2 - Heavy Melee
2 - Light Ranged
3 - Heavy Ranged
1 - +Special Property (Reach, Automatic, etc)
1 - 5 Rounds
1 - 5 Fuel
1 - 5 Power
3 - Explosive

Enemies

You can build enemies quickly using the following procedure:

  1. Assign one low stat of 4, one high stat of 18, and make the rest either 12 or 8.
  2. Calculate HP as 10+CON.
  3. Outfit with appropriate weapons and armour if they're prone to it.
  4. Calculate Armour, or just assign Low (10), Medium (20), or High (30) Armour.
  5. Give them a flavourful ability of some kind. Remember to attack the whole character sheet.
  6. Roll on the mutations table (I'd roll 3d20 I guess).

For more sophisticated monster creation you can follow the rules you like from other d20 systems, but I'd suggest doubling or tripling the bonuses they get to their dice rolls.

Here are a few pre-built monsters for you:


Name (Description)
HP: 1+CON Armour: Calculate
STR: 11 CON: 11 DEX: 11 INT: 11 WIS: 11 CHA: 11
Attack: Weapon: 1d20+11, 1d6 damage. Special Move: Move Name: Effect.
Inventory: Some stuff.


Chaff

Scummy ne'er-do-wells inured to violence. Often in the employ of someone meaner and more powerful.


Toobers (Just your bog-standard desperate shmoe)
HP: 14 Armour: 14 (rags)
STR: 12 CON: 4 DEX: 14 INT: 4 WIS: 10 CHA: 3
Attack: Bent Knife: Light, Melee, 1d20+14, 1d6 damage.
Inventory: 1 Ration, 1d4 Scrap.


Snick (A clever little rascal)
HP: 13 Armour: 12 (dark cloak; +5 to sneaking)
STR: 4 CON: 3 DEX: 12 INT: 17 WIS: 14 CHA: 7
Attack: 5 Throwing Knives: Light, Ranged, 1d20+12, 1d6 damage.
Special Move: Pocket Sand: Target must pass a difficulty 22 Dexterity check or be blinded for one round.
Inventory: Lockpicks, 1d4 Bucks, 1d4 smokes.


Hammer (Inserts people into the wall by hitting them on the head)
HP: 25 Armour: 19 [Negate 2] (heavy armour)
STR: 19 CON: 15 DEX: 5 INT: 6 WIS: 9 CHA: 10
Attack: Iron Axle: 1d20+19, 2d6 damage.
Special Move: Bull rush: 1d20+19, target is knocked prone.
Inventory: Bottle of rotgut.


The Motley Crew

Strange thugs who run things down below.


Chopper (Long spinning limbs, looks a bit like a helicopter)
HP: 15 Armour: 28 (Light Armour)
STR: 7 CON: 5 DEX: 18 INT: 12 WIS: 9 CHA: 2
Attack: Sawzall: Light melee, Power, Automatic. 1d20+18; 2d6 Damage. Special: Stretch Armstrong: Reach applied to all melee attacks.
Inventory: 6 Power, Bowler Hat, Sunglasses, 2d4 Bucks.


Hotdog (A.K.A.: The Fireman, covered in blackened scales)
HP: 29 Armour: 20 [Negate 2] (Heavy Armour)
STR: 14 CON: 19 DEX: 3 INT: 6 WIS: 8 CHA: 1
Attack: Flamethrower: Heavy ranged, Fuel, Automatic. 1d20 + 14; 3d6 Damage. On a hit, targets take an additional 1d6 damage at the end of their next turn.
Special: Fireproof: Immune to flames.
Inventory: 20 Fuel, bottle of lotion, 2d4 Bucks.


The Dreamer (Half in and out of consciousness)
HP: 14 Armour: 14 (predicts the future)
STR: 5 CON: 4 DEX: 3 INT: 19 WIS: 15 CHA: 11
Special Move: Foresight: Allies nearby get +15 Armour while The Dreamer can talk to them.
Inventory: Bathrobe, 2d6 Bucks, Bottle of essential oil.


Big Killer ('Roided out guns guy with an extra arm)
HP: 22 Armour: 18 (light armour)
STR: 17 CON: 12 DEX: 8 INT: 4 WIS: 6 CHA: 4
Attack: Uzi: Light ranged, rounds, rapid-fire. 1d20+8, 2d6 damage.
Attack: Machine gun: Heavy ranged, rounds, rapid-fire. 1d20+17, 3d6 damage.
Special: Bloodlust: If Big Killer does not damage an opponent on their turn they take 1d10 psychic damage. If they run out of ammo they fall unconscious and froth at the mouth.
Inventory: 25 Rounds, spare uzi, 1d4 Bucks.


Monstrosities

Awful, awful things.


Tube Boogies (Wretched mounds of half-formed flesh that travel in herds)
HP: 26 Armour: 20
STR: 18 CON: 16 DEX: 4 INT: 1 WIS: 9 CHA: 1
Attack: Flesh Whip: 1d20+4, 1d6 damage. Attacks twice.
Special: Weak Flesh: Takes double damage from electricity or fire.
Special: Split: Splits in two when hit with a melee attack. Divide the damage evenly between both.
Inventory: 1d4 Scrap, 1d4 Bucks, 1d4 Rounds.


Elite Forces

Kids paid just enough to keep them loyal, kitted out in top of the line gear.


Guard with combat armour immune to electricity, +5 Assault Rifle

Special thanks: Andrew Stevenson, who proposed some truly unhinged mutations, and to Christian Hendriks for some fun whimsy and proofreading. Further thanks to bread wizard and that ordinal person on Mastodon for good flair ideas.