[The Lyonesse RPG costs £59.99 in print+PDF and is 512 pages long. The Gaean Reach RPG costs £6.95 in PDF and is 108 pages. Dungeons & Dragons is available in various formats, and from various publishers.]
Emulating Vance has been a central element of RPGs since their inception; arguably, he is the most important single literary influence on D&D, and the sheer range and popularity of his novels has inspired RPG designers for decades. Two recent examples are the Lyonesse RPG and The Gaean Reach RPG, which between them neatly demonstrate the pitfalls confronting designers hoping to imitate or emulate Vance's fiction.
The Gaean Reach is the biggest sinner of the two. I must confess that I am not in general a fan of Robin D Laws' game design, and I particularly disliked his Dying Earth RPG (which also, of course, tries to imitate Vance). So my review is clearly coloured by my own personal preference. But with that said, I think there is something fundamentally misguided about the premise of the game, which it seems to me seeks only to achieve a thin, superficial pastiche of a small category of Vance's fiction in RPG form. Rather than drawing from what I would take to be the real joy of reading the Gaean Reach books - which is the way Vance glories in the sheer variety of the worlds he creates, and the variety of stories they allow him to tell (mystery, thriller, romance, space opera, revenge travelogue, picaresque, action) - the game instead, in true storygameish fashion, tightly focuses on providing the tools to just tell and re-tell a narrow and rather boring sub-Demon Princes tale of vengeance. We don't get the means to create a great interstellar sandbox to explore, with Vancian themes (more below). Instead we just get a way to randomly generate a bad guy ('Quandos Vorn') who the players are supposed to go out and revenge themselves upon. It's all very, to use that RonEdwardsism, "coherent".
In other words, we what the game provides is ultimately simply a way to artificially create a replica of the plot of a Demon Princes novel with our friends, together with the kind of overblown, pseudo-Vancian 'witty' prose which so marred The Dying Earth RPG. Reading it is like eating fish and chips in an 'English' themed pub in Tokyo: not as good as real fish and chips, and you don't really eat fish and chips in a pub to begin with.
If the problem with The Gaean Reach is its laser-like focus on pastiching The Star King, the flaw in the Lyonesse RPG is that it sits at the opposite end of the spectrum: it simply faithfully presents the setting of Lyonesse as a typical, bog-standard fantasy world - the kind of gazetteer that was ten a penny in the fantasy gaming scene during the 80s and 90s. Shorn of Vance's prose, ideas, and themes (again, more on that below), Lyonesse just isn't particularly interesting or different as fantasy settings go - and a rather detailed overview of it (combined with some rules) is all the book really provides. Are you interested in the five crimes that are punishable by death in each of the Ten Kingdoms? Do you really need to know that Blaloc is a 'sleepy, inconsequential kingdom'? Does it matter to you that 'richly coloured fabrics' are readily available in Port Posedel? Perhaps so, but I have to confess that reading the novels seems a more enjoyable and valuable activity - not to mention a better way of getting to know Lyonesse - and D&D a perfectly suitable system in which to run a game set there afterwards. If all I'm getting is a rather ordinary fantasy continent in which to set a campaign, £59.99 seems a steep price to pay. The book looks great, no doubt about it. But does it feel like Lyonesse? Not really.
But that brings me to my main point, which is that, for all people might endeavour to design RPGs set in Vancian worlds and emulate Vancian fiction, in actual practice it is 'old school' D&D which - at the table - captures the tenor, tone, and philosophy of Vance's work most perfectly. Whether by accident or design, what really happens when people sit down to play OD&D is that Vance's themes organically emerge. The sense of slightly arch and ironic detachment, oddly reminiscent of pre-modern fiction, eschewing interior monologue, or indeed the interior world of the characters, except obliquely. The sudden shifts in tone, from comedy to tragedy, from the sublime to the ridiculous. The matter-of-factness of violence and danger, which is always and everywhere underdramatised and all the more dramatic for it. The slight sense of gleeful schadenfreude that accompanies unfortunate events, particularly where the proud are brought low. The methodological individualism of Vance's worlds, where it is actions that matter and everyone is ultimately a master of their own fate. The fact that everybody, from the lowest shopkeeper to the mightiest villain, has motives, desires and interests of their own, rigorously pursued. Emulating Vance is about emulating those qualities of his fiction - the themes which he returns to in every novel, working and reworking endlessly into new and more interesting shapes - and D&D in my experience somehow manages it again and again at the table when the spirit of the original rules are adhered to. It's not, in the end, about aping Vance's plots and language, as The Gaean Reach RPG does, or simply using his furniture, as in The Lyonesse RPG. It's about a way of approaching the fiction that unfolds in play - and it's D&D that does that best.