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When Worlds Collide RPG Review

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When World’s Collide is universal multi-genre RPG produced by its UK based namesake company, consisting primarily of it’s author, John Fountain, and editor, Alistair Dandy (Yes, this game has an editor, and it shows). I was graciously provided with a review copy of the PDF, at my request. The game describes itself as “

When worlds collide, reality is no longer trustworthy. Within this book you will find all the rules needed to create characters and run games within the infinite multiverse. The game provides a comprehensive platform to run any adventure in any genre, be it sci-fi, fantasy, horror, super-hero or cyber-punk. Characters can shift between universes to experience other realities. Games-Masters can choose to throw characters across the multiverse; one week they are in the old west, the next gothic horror or a future of biotechnological marvels, and the following week? Who knows?”

My summary? When Worlds Collide (WWC) provides a competent exhaustive universal ruleset, well-written, well-edited, and pleasingly presented, that does a poor job of communicating the high-concept underlying it’s multi-verse. The high-concept,  which drives the world-hopping and immersive exploration of the limitless environments that can be created with the rules. The ‘default’ GM as mystery keeper play assumption, along with its focus on ‘participationist’ play by the group, stifles the ability of the the text to sell its harrowing junket across the boundaries of an inimical, many-splendored multi-verse through-line. An indifferent multi-verse where frequent flyers gain access to a list of detailed flavorful powers operating via in-depth multiversal laws at the cost of body-horror side-effects, from the embarrassing to the Cronenbergian. A multi-verse were dark truths and greater forces are at work, ready to quantum entangle our intrepid world-hoppers.

Lets Break it Down.


The game is presented as 527 page PDF. Laid out in a spacious two-column format with a variety of artwork included to break up the text. Tables are presented as stylized boxes, along with various call-out boxes for rules examples, asides, etc. Interestingly, it consists of mainly stock-photos, most from royalty-free stock photo sites on the next, which gives it a more ‘realistic’ look. A nice change of pace from the more commonly used stock art collections you find in many PDF products.


The rules core used in WWC are the Tri- Hexahedral Engine (THE) System. It is a competent core mechanic that the rest of the rules build on. Roll 3d6, add modifiers (based on stats & skills) against a Difficulty Level (DL). Stats are presented as 0-based +/- scores ranging from –3 to +5 for most characters. Characters may have expertise and specializations that will add a couple more points to this, as well as some special abilities.  The average DL is 10, and the mods are small, so pretty easy to use. It features an interesting ‘critical success’ mechanic based on the number of sixes rolled, 2 sixes rolled equals a level 2 crit success, and 3 is a level 3 crit success. This is independent from the margin of success/failure. 

It Is functional and utilizes tried and true design patterns for the most part.  In addition, the rules include lots of explanatory material, overviews, examples, and summaries that make it really easy to learn. It is equal the mass of the rules. Many other games would do well to match its friendliness.


WWC features an interesting character creation system with race and character ‘age band’ providing the main limits on character creation. Characters are given a broad ‘vocation’ class, which gives bonuses to skill-sets, such as academic and technological (AC&T). These are much like the skill group aptitude bonuses in BRP. Within that vocation they chose an Occupation which determines their key expertise and elective skill options. Character have 7 stats (Attributes in most other systems), the most notable of which is biomorphic integrity (BIO). Which operates as an overall Body stat, as well as key stat in the character’s ability to avoid the insidious effects of traversing rifts between worlds. There are 15 attributes (derived stats) many of which effect rift travel.

Next is a detailed skill system, divided into the skill-sets above. Skills have expertises, which operate like a familiarity for character’s attempting some tasks in which they lack root expertise. In addition, you can have specializations in subsets of expertise, a cascading skill-tree system. They are about as detailed as GURPS skills. The skill description also feature a lot of amusing epigraphic quotes, showing off the authors’ British humor.

Lastly character have Special abilities. These run the gamut from perks and talents, to full on powers in other systems. The special abilities are finely detailed much like GURPS. With abilities such as Lip Reading and Literacy. While the power system is rather flavorful list including powers such as Dendromerge (merge with a tree like a Dryad), Body Pocket (like a Kangaroo), Ectoplasm (You can generate ghost slime!), as well as the usual flight, energy blasting, etc.

The powers system has a detailed ‘unified theory’ as how to it works, that ties into rift traversal and the rest of the meta-physics of the game. Powers are finely detailed, constructed by choosing range/effect, uses, and stress or corruption they cause. The accumulation of corruption is a major hazard of traversing rifts into other worlds. Powers operate as one of two modes “Psionics”, relying on the characters personal energy to affect from the world from the inside out, and based on the character’s BIO ability. The other is “magic’, which relies on the shaping of external reality, and is based on the character’s MIND stat.As I mentioned, there is a well-thought cosmology and meta-physics underlying the game universe.


The combat system is a fairly standard blow-by-blow action implementation. Determine initiative, declare actions. Combat roll is your task roll versus enemies. The 3d6 roll can be used as hit location. All fairly standard, except for its damage system, which is a bit muddy.

WWC’s damage system uses a ‘Body/Stun’ type damage system, called Life Points (LP), and S-INC (Stun- Incapacitation). I found the system a bit confusing to figure out because of the way stunning weapons work.  For Stunning weapons, you compare the damage roll to your current SINC total, if over target is stunned, with duration based on margin. That is, stun weapons compare the damage total to the character’s current SINC. A simple threshold resistance. Stun FX weapons also cause a small amount of LP.

Killing weapons do LP, plus a small amount of SINC.  So stun is both an ablative point total via your SINC points, and a dice target. I found that a bit confusing. Also, massive damage of more than half your LP, or SINC, in a single hit, is a crippling result and will take you out of fight. If your reduced to 0 SINC, then excess damage goes to your Life Points. As I said, I found it kind of muddy implementation.

There additional special rules for all manner of situations and attacks, as befits a universal system. Which to look to be functional.

Weapons and armor are given generic damage classes, of light, medium, heavy, on up to colossal, with the weapon specifics glossed over, other than it’s damage type, i.e. Blunt Force Trauma, Hack, Stab, Energy, Ballistic. With weapons doing a different die type with an damage category. Light melee weapons do 1d8+ character’s damage bonus., while light ballistic do 1d10, for instance. Weapons can also have additional special attack effects, such as being cleaving/impaling. Rules are included for hit location effects and other details.

There are rules for all manners of hazards characters might encounter across various worlds. As well as additional rules for various adventuring situations. All look to be functional. This section has a very GURPS feel. Of character’s detailing with hostile environments from an immersive first-person level.


one of the major themes of the game is the accumulation of stress as characters encounter the impossible, the disturbing and horrible among their adventures. This is one of the more interesting elements of the game and its cosmology. It reminds me a lot of Kult’s light/darkside points as well as Unknown Armies meters. Chthulhu’s SAN loss mechanics are an obvious influence. I am reminded of these systems, in that as characters gain more stress and deal with more events they can develop psychological problems, or even develop mutations and deformities in the case of rift travel.


The Rifts chapter presents all the details of traveling between worlds, which is mysterious and can cause all manner of complications for a character. The game provides a rich cosmology and meta-physics for describing rifts, and the mechanics of traversing them. It is one of the major selling points of the system. It provides all kinds of goodness for facilitating world-hopping and exploring worlds. The author was influenced by Michio Kaku’s books Parellel Worlds and Hyperspace. (The author includes a hefty bibliography, much thought and research went into the creation of this game.)


I felt the rules fell down in this section, as not enough attention was focused on running a  WWC game, as opposed to general game mastering advice. I felt the default playstyle, of a “mystery-keeping’ GM, leading players through exploration, limits the reach of the game. A world-hopping universal rules set as this can work very well as a more collaborative setup with troupe style play. As it allows all the players to be keyed into the cool bits of the setting, in this case the meta-narrative and cosmology behind WWC. Rather than limiting themselves to the pin-hole of a single GM in a high-effort game setup.


Overall, I like When Worlds Collide, it is a competently designed system, very well written, and well-edited. It delivers the goods for running a multi-genre universal game. The cosmology and meta-narrative behinds the Rifts and cross-world travel is quite compelling, and opens all kinds of dark and desperate and bizarre storylines. However, the game does a poor job conveying that to the prospective reader.

It has to be pieced together by reading through the Rifts rules section, the powers, and finally GM section. In addition, the assumed ‘GM as Mystery Keeper” play style can seem off-putting as it puts a lot of onus on the GM, and can keep the players from ‘getting to the good stuff’. A revision of the rules that brings these “Why play this game instead of X” elements to the forefront and makes this easily graspable by the players, along with more ways to explore the game space, would improve the appeal of this game. As it stands, it can be overlooked as ‘another’ universal rules system.


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