I’ve been working on a roll-and-keep variant of Synthetic Dream Machine for a possible upcoming Ultraviolet Grasslands game, because while I like what Synthetic Dream Machine/SEACAT is putting down, I’m less enamoured with the d20 core. In addition, I also wanted to get hit and damage in combat down to a single roll. This is nowhere near done yet, but after I posted about it on Bluesky, people wanted to see it, so here it is. As per usual, comments can be directed towards any of my socials.

Character sheet here.

Base rules

Initially taken basically verbatim from Synthetic Dream Machine, modulo the different stats, but is now its own thing. Much of the actual text is still from SDM though.

Roll

2d6 + ability modifier + skill against target number:

• 4: trivial. Only relevant for critical failures (snake eyes)
• 6: easy
• 8: mediocre
• 10: hard
• 12: very hard

All 1s always fails. Rolling the maximum value on all of your kept dice lets you keep another die rolled. If you have no other rolled dice to keep, roll a d4 and keep it. If that’s a 4, roll another d4, and so on.

Advantage and Disadvantage

Advantage grants bonus dice. Regardless of how many dice you roll, only keep two (unless a special rule says otherwise).

Disadvantage grants penalty dice. Each disadvantage die reduces the highest non-negated die with equal or lesser value to 1.

Advantage and disadvantage dice start at d4 for minimal effect and go to to d12 for extreme. Usually they’ll be d6.

Gear

Gear grants advantage dice. Better gear grants more dice or dice with larger sides.

Level

Measure of power. PCs start at level 1 and go to level 10.

Stress

Resilience, basically. Think hp. After it goes to 0, injuries accumulate.

Abilities

Range from 3-18, with the Basic D&D spread. A 1st level PC can either roll or assign. If they roll, keep rolling until at least one ability is at least 13, then optionally swap any two. If they assign, assign an 8, 9, 11, and 13.

When listed in the text, the full ability name denotes the ability score, and the three letter abbreviation denotes the ability modifier.

• Strength (STR): bulk, toughness, power
• Agility (AGI): speed, agility, etc
• Aura (AUR): force of personality, charisma, mental resilience
• Wits (WIT): creativity, problem solving, thinking quickly

Skills

Freeform. Up to one skill at a time can apply to a roll, when it makes sense. Can be a job, something narrower, or something weird. Level 1 characters start with 3 skills at skilled level.

After level 1, you can stack more skill points onto a skill to increase its bonus:

• Skilled: +2 bonus
• Expert: +4 bonus
• Artisan: +6 bonus

You can get skills during play with time, training, and effort.

Injuries

Two sets of injuries: physical and mental. Each set has a number of slots: 3 + STR for physical and 3 + AUR for mental. Each time you get injured at 0 stress, add another injury to the next open slot of the corresponding type.

Each injury applies a 1d6 disadvantage die on all rolls until healed. If you take an injury and the entire track you’re taking it to is already full, you begin dying. When dying, you may either make a last stand or defy death.

If they make a last stand, they immediately make a single check for whatever it is they want to do, ignoring disadvantage and converting all spent hero dice to d12s. After making their last stand, they die. Always.

If they defy death, they fall unconscious and survive, but must immediately roll on the doom table. If they were bleeding out they stop bleeding, if they were on fire the fire goes out, etc. Unless an enemy hacks them into hamburger meat, they’ll live, somehow.

Doom

1d6	Effect
1-3	Minor wound: reduce a random stat by 1. This damage can only be restored by suitably powerful magic or science.
4-5	Major wound: reduce a random stat by 1d3. This damage can only be restored by suitably powerful magic or science.
6	Doomed: you’ve stood at the grey gates of the kingdom of death and returned to tell the tale. The next time you begin dying, you may not defy death. This condition can only be removed with extremely powerful magic or science whose acquisition could form an entire arc of a campaign. Characters should never have easy access to the ability to remove Doomed.

Saves

Blind luck roll. Roll ability score with no skills or other bonus dice, and try to get 9+.

Defense

Ascending AC. 5 + AGI + skill + armor.

• Light: +1 AC, 1 bulk
• Medium: +2 AC, 2 bulk
• Heavy: +3 AC, 3 bulk
• Shield: +1 AC, 1 bulk, 1h

Rounds

Couple seconds. Or more. Or less.

Initiative

Troika style. Alternatively, tarot style.

Action

Move, then do a thing.

Attack

• Melee: roll STR + skill against target’s defense.
• Ranged: roll AGI + skill against target’s defense.
• Oldtech: roll WIT + skill against target’s defense or AUR + skill, depending on the attack type.
• Psychemagic: roll AUR + skill against target’s defense or AUR + skill, depending on the attack type.

Don’t forget to add the bonus gear dice if you have a weapon!

Damage

Successful hits deal damage equal to difference between roll and defense, minimum 1. NPCs die at 0 stress. PCs accumulate injuries.

Some attacks target abilities. They deal 1d3 damage by default.

Healing

PCs heal 1 stress per day per level. If they spend an entire week at full stress with no danger, they heal one injury.

Inventory

For every trait or item beyond their limit, suffer -1 to all rolls.

• Items (stones/stone-sized objects): 8 + STR
• Traits (skills, mutations, innate powers): 8 + WIT Curses, diseases, other afflictions also occupy inventory slots.

Magitech and Fantascience

Take 1 damage per power level. D&D spells have a power level of double their spell level. Cantrips are power level 1.

You can get powers in play in multiple ways. Spell-like powers can be acquired as items. Innate powers and mutations can be acquired if the fiction demands.

Hero dice

d6s you can add on rolls as advantage. Each PC starts with 1 per session, or the number you ended last session with, whichever is higher. PCs can also gain them for being cool or also just every hour or two. You can never have more hero dice than your level.

Experience

• Carousing: waste 1d6 x 100 (or more) cash to gain that amount of XP. Roll WIT on carousing table for side effects
• Exploring: 1d6 x 10 xp for braving danger to see something new
• Quests: 1d6 x 100 xp per session of progress towards goal

Leveling up

XP	Level	Stress	Benefits
0	1	4	Starting skills. May trade one starting skill for power/mutation/talent
300	2	8	Increase max stress or gain a skill point/power/mutation/talent
750	3	12	+1 to two ability scores
1,500	4	16	Increase max stress or gain a skill point/power/mutation/talent
3,000	5	20	+1 to two ability scores
6,000	6	22	Increase max stress or gain a skill point/power/mutation/talent
12,500	7	24	+1 to two ability scores
25,000	8	26	Increase max stress or gain a skill point/power/mutation/talent
50,000	9	28	+1 to two ability scores
99,999	10	30	+1 to two ability scores, increase max stress or gain a skill point/power/mutation/talent

When you choose to increase max stress, increase your max stress by +1 per character level. Recalculate this bonus every time you gain a new level. Stacks when taken multiple times.

Content

Weapons

Weapon	Die	Special
Light melee	1d6	Can be dual wielded with another light melee. When attacking with two weapons, add both weapons’ advantage dice to the attack.
1h melee	1d8
2h melee	1d10

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