The marketing motto for Warhammer 40k 10th edition promised it would be 'complex, not complicated'. That's an admirable game design goal and an excellent sales pitch, but boy oh boy, it's also the kind of manifesto promise that a critic like me can make hay with. 10th edition is not simple, but the problem isn't that the designers failed to make a simple game - it's that the pursuit of simplicity itself ended up making the game more complicated.
Playing 10th edition Warhammer 40k requires a supplemental 35 page document packed with updates and commentary on the core rules, a Warhammer 40k faction pack with the current errata and expansions for your army, and a further three update documents if you're interested in matched play. How did it get this way?
Lets use an example from the core rules update, the rules for pivoting models as they move. I had to look them up recently because they're frustratingly easy to forget and require five pages of text and diagrams to fully explain. In summary, models without bases (usually vehicles and monsters) or with irregular bases (like Imperial Knights) must use up some of their movement allowance the first time they pivot during their move.
The rule in the core book takes up a couple of sentences and in most cases has an almost identical effect. This states that "the distance a model moves is measured using the part of its base that moves furthest along its path", and "if a model does not have a base, measure using whichever part of that model moves the furthest". That statement contains a multitude of the sins of simplicity.
First, there's invisibility. The original core rules appear at the end of the paragraph for moving units, don't appear in the summary of that section, and don't have diagrams. They're easy to overlook and easy to forget. Not everyone will miss them, but if two players who understand the rules differently meet, you have the basis of an argument.
Then there's ambiguity. The distance a model moves is measured using the part of its base (or hull) that moves furthest along its path. But when, exactly, do you need to track the displacement of that part of the base? It could just be the distance between the first and final positions, but as vehicles can't move through many forms of terrain, they may need to pivot, perhaps more than once, to complete a move - so do we need to account for the displacement of the model part we're tracking for every pivot? The results are different.
Another problem with simple rules is inadequacy. The core rules update explains how to handle moving models that overhang their bases through gaps between terrain which can accommodate the model's base but not the model itself. The core rules don't include an explicit provision for this - but Warhammer 40k is a system in which both the physical model and its base can be relevant to the rules, and clearly enough people had trouble with this rule that GW felt a clarification was necessary.
It is possible to simplify a ruleset without running foul of these problems, but there's a big tradeoff. Making rules simple, unambiguous, and easy to remember, can only be achieved if you try to make the rules cover fewer scenarios. You can reduce variation between units, use fewer subsystems, or make those subsystems less expressive - in a word, abstraction. The results can still be great games - Grimdark Future or Kings of War stand out as good examples - but they have a narrower scope.
Truly simple design has never stuck to Warhammer 40k. 1998's third edition was a radical overhaul that stripped the game to the bone. But it was too abstract to fully express the fantasy that fans and designers wanted from 40k's. So rules got added in bit by bit, via Warhammer 40k codex releases, errata, FAQs, White Dwarf supplements, and new editions. By seventh edition we had the worst of both worlds - many extremely complex sub-systems wired into an abstracted base rules set.
Every designer wants to create the most elegant, efficient set of rules they can for their game, and that's a great goal. I just hope that for Warhammer 40k 11th edition, the designers don't set their sights too low.
What do you think - how would you make Warhammer 40k simpler? Or should we just accept that it's a more complex game than it's marketed as? Let me know what you think in the official Wargamer Discord community.