Chance would be a fine thing

To allow for a bit of differentiation between classless characters in my heartbreaker rpg, I'm including a separate mechanic in addition to attribute tests - chance dice.

(N.B. possibly helpful to note at this stage that attribute tests - for task resolution - are now being treated similarly to The White Hack mechanic: Difficulty Rating ≤ d20 roll ≥ Attribute Value.)

Respectfully ripped off from The Black Hack's usage die (TBH) and Macchiato Monsters' risk die (MM), with a nod also to Pulp Alley's gameplay, the chance die represent the uncertain diminishing of a resource. Roll the die: on a 4+ you keep the die, but on a 1 to 3 the die is 'downgraded' to the next smallest die (e.g. d8 to d6). If a d4 is downgraded, the resource has run out.

(I've gone with MM's choice to change the failure of TBH's usage die from 1-2 to 1-3 because a) I'm used to to Pulp Alley's 4+ system and b) I like the fact that when the die is reduced to a d4 you know that the next use of the resource will probably be the last - a character should have an inkling that something is about to run out.)

It removes intricate bookkeeping but still allows for a resource management-focused game. TBH also used it for working out the duration of drugs & diseases, and MM pushed the use to pretty much every aspect of adventuring. I'm somewhere between the two. In addition to tracking consumable items like torches and rations, I want to use it to cover the three elements of fantasy rpgs that classes usually cover: combat, skill and magic.

Armour

In an effort to keep combat a player-facing experience, all NPCs will deal their average damage on if a character unsuccessfully defends (usually their Level/HD +1). The Armour Chance Die roll (ACd) adds the random element - whatever it rolls is subtracted from the average damage to a minimum of 1. If it rolls 1-3, that represents wear and tear. Armour can be repaired one step every rest.

The ACd depends on the armour being worn.

Luck

After rolling an attribute test of any kind (though I'm tempted to open this up to any roll), the play can also roll their Luck Chance Die (LCd) and modify the original roll by up to that amount. Rolling a 1-3 represents quite simply a character's luck running out.

A character starts with LCd6, and may upgrade this with enough experience to a maximum of LCd10.

Magic

Pretty much an adaptation of the GLOG casting system, a character casting a spell rolls a number of MCd equal to the level of spell they want to cast. Any doubles result in a magical mishap, any triples in a much, much worse mishap. Some spells use the total of the dice rolled. The MCd is downgraded for every 1-3 rolled, showing the caster's increasing mental exhaustion.

A character starts with 1MCd6, and may upgrade and increase the number with enough experience to a maximum of 5MCd10. Most won't start with any spells.

This will invariably make magic rather powerful (as it should be), but players not being able to choose their spells from a list should mitigate this, and if things go wrong they do so spectacularly (as it should be).

I like presenting players with options, and as players advance their characters they will have to be weighing up between going for greater power (more MCd for casting higher levels) and greater control (higher MCd for reducing risk of doubles and triples).

In that vein, I want to add an extra use for ACd and LCd so that players don't automatically reach for them if they want to resist damage or improve their roll. Hence:

Injuries

If reduced to 0 Stamina, the character must roll in the Injuries Table. For physical injuries, roll both your LCd and ACd and take the highest, then subtract any Stamina lost caused beyond 0. For mental or magical injuries, roll both your LCd and MCd and take the highest.

When an injury is rolled, the mechanical effects should be interpreted with a descriptive wound.

Injuries each take up a Slot and have an Injury Chance Die (ICd). At each night's rest roll the ICd. On a 1-3 the die is downgraded to show that the injury is getting better. The injury continues to take up a Slot until it is downgraded from an ICd4. At this point any ongoing mechanical effects are also removed, though narrative injuries (such as a missing limb) remain.

 The character remains at 0 Stamina until a rest allows then to regain some.

Injury Table
Total	ICd	Injury
0 and under	n/a	Dead Roll up a new character!
1	ICd12	Dying Dead in d6 rounds unless an ally helps them with a WIS test. (difficulty rating = how much damage the character took)
2	ICd10	Lose d4 from a random attribute.
3	ICd8	Lose d4 stamina every test for a random attribute.
4	ICd6	Disadvantage on all tests for a random attribute.
5	ICd4	Your stamina may only increase up to half your CON.
6	ICd4	You always go after NPCs in the turn order.
7 and above	ICd4	No further ill effect.

Look at that, a bona fide HTML table right out from the 90s!

Now the player has to ponder whether they ought to save their ACd or LCd for the injury table, though doing so only enhances their chances of not dying. Getting injured is still pretty brutal, if nothing else but for the loss of item slots.

As an aside these injuries also allow a character to continue to take part in a scene rather than a player having to sit out a couple of rounds, at the greater risk of more injury / death. Always give players the option.