In my old age, the thought comes to me to remake it, to storify it.
I suppose the best thing would be to change it to some story game such as Gumshoe's Swords of the Serpentine. Kevin Kulp's play reports sound like something out of a Moorcock novel.
But...
I still love the bones of the old Chaosium system. So here is a stab at Storified Stormbringer.
First and foremost, how can we give narrative agency to players?
The underused Power attribute seems a good bet. Not only are high POW characters likely to be sorcerers with access to world changing magic, all players now can use POW points to influence the story and game world. This also means that these story game rule additions can be easily ported to other literary inspired Chaosium games (ie Call fo Cthulhu, Ringwolrd, or Elfquest) with little work.
STORY RULE 1 - USING POW
Players can choose to use their pool of POW points to invoke Minor or Major Boons. Minor Boons are small advantages to rolls, and POW points used in this way can be regained fairly easily. Major Boons can change something about the scene, the story, or the entire game world, and replenishing POW points used in this way becomes a major undertaking.POW thus becomes also a pool of points that can be used for various story effects, giving agency to the player much like other story mechanics.
MINOR BOONS
Minor boons are simply bonuses to rolls. Players should declare they are invoking a Minor Boon, then narrate how the bonus is justified - do they have special knowledge, or are they motivated to make a greater effect? Don't just say "I want +1 to damage," instead, narrate the event, "I remember my slain friends' faces and slash hard into the Duke of Hell! Can I get +1 to damage?"Per 1 POW point spent
+5% to a d100 roll+1 to a damage roof
-1 to damage taken
-5% to an opponent's d100% roll
Remember, these bonuses are available if the player declares they are spending points BEFORE the roll. If the player wants to invoke a Minor Boon AFTER the roll has already been made, they must pay DOUBLE (ie 2 POW points per plus or minus 5% or 1 damage). This lets players strategically decide to take a risk at low cost declaring before, or pay a higher price to change fate after the die have been cast.
Note:
1) Players may only invoke Minor Boons for their own character - they may not use POW points to alter rolls for other PCs.
2) POW used for Minor Boons reduces the POW score for magic purposes, so any summoning should wait until POW points are replenished as outlined below.
3) Each character can invoke one Minor Boon per session.
MAJOR BOONS
Major Boons don't give mechanical bonuses or penalties, rather they change the narrative flow of events in myriad tangible and intangible ways. Only one Major Boon per session is allowed, and the GM should keep scrupulous track of its repercussions.
Change the scene = 1 POW point
Change the story (scenario or adventure) = 2 POW points
Change the game world = 3 POW points
Major Boons should be narrated eloquently, matching the tone of the game and the theme of the story. They shouldn't be game breaking non-sequitur Get Out of Jail Cards. The GM is free to deny any Boons, minor or major, that make no sense in the world or story.
Major Boons can be deployed before or after events, within reason.
Examples
Scene Change - If players are fighting on a ship's deck, a player character can ask that a rogue wave comes and either reduces the number of foes or gives the PCs time to escape.Story Change - Players can turn an NPC jailer into an ally because they were childhood friends or fall in love at first sight, or find a clue to the MacGuffin from an old beggar man, or stumble onto a magic weapon while running from ghouls in a forgotten tomb.
World Change - A PC can suddenly remember that Melniboneans are scared of cats, or that Isle of Purple Town ships all carry rum that can be turned into fiery cocktails to repel pirates.
Note:
1) Players may invoke Major Boons for any character - they may use POW points to alter circumstances for other PCs, if it is well thought out and entertainingly narrated.
2) POW used for Major Boons does not reduce the POW score for magic purposes, but does reduce it in terms of Boons, Minor as well as Major, that can be used in future. Basically, this models a character's luck running out as they call in favours from fate. You should start keeping track of POW for magic and POW for Boons separately. A minor inconvenience, but worth the effort.
3) Only one character can invoke a Major Boon per session, period. Major Boons are to be used sparingly and only in times of great need.
REGAINING POW
POW points used in Minor Boons are all replenished after a short scenario or part of a longer adventure. Basically, if the PC has some downtime, POW is regained at a rate of 1 per day not adventuring.For POW lost in Major Boons, the PC must do something that furthers the story, at the guidance of the GM. This could either be something in the PCs backstory (ie return to their ancestral village and face down the enemy tribe that harangue them), or the larger story of the adventure (ie sneak into the harem of the Pan Tang emperor to free the winged folk princess kept there).
STORY RULE 2 - CRITICAL HITS
When I ran Stormbringer back in the day, the biggest complaint from my D&D players was the high chance of critical attacks and, more alarmingly, the high change of a devastating roll on the Wounding & Maiming tables. Here is a way to give agency back to players and increase tension when criticals are rolled.
When a critical (1/10th of weapon skill) is rolled and not parried or dodged, there are three options:
1 Roll double damage. If this does over half HP damage, roll on the Critical Damage chart.
2 Roll normal damage, ignore armour. If this does over half HP damage, roll on the Critical Damage chart.
3 Roll no damage, instead roll on the Critical Damage chart.
(Note: A critical attack can only be completely avoided by a critical defence. If a critical attack is met with a successful parry, damage is halved, and major wounds are only temporary, healing are 1d6+1 days of rest)
When fighting NPCs, the player gets to choose which effect whenever they hit or are hit with a critical attack. This gives them some advantage both to end fights quickly and survive an unlucky roll.
When PCs are fighting each other, both the attacker and defender secretly write their preferred number on a slip of paper, then at the GM's sign, show their choice. If both have written the same number, that effect is applied and play continues. If attacker and defender have written different numbers, they then play Scissors Paper Rock, with the winner's preferred number effect being applied.
Seems like a bit of a laugh, can't wait to test it!
OTHER BIBS AND BOBS
You could also steal my Call of Cthulhu encumbrance and reaction rules HERE.