What’s Illusionism, and why should you care while running a game?Illusionism is a method of setting building or adventure design that raises the question of player choice or agency. It’s the practice of Game Masters or designers of changing encounters or events in game that will follow a specific path or create a specific scenario. The term itself is sometimes used pejoratively - but like most other things in a hobby or fandom that get people angry it’s a nuanced issue with multiple perspectives. Obviously GM actions that force specific results or events can be a problem for players when the players feel that their choices will lead inevitably to the same results. This is somewhat like the tendency of players in of computer RPGs to skip through cutscenes and dialogue because they expect that decisions about plot developments or the motivations and plans of their characters are pre-scripted or will inevitably lead to the same result.
In a tabletop game roleplaying the plans and motivations of both player characters and NPCs or factions in the setting are an area that tabletop can manage extremely well with a GM there to make the setting react reasonably to unexpected plans, shifts in allegiance or changes in player goals. In a video game the next adventure or scene has already been scripted and designed and cannot be modified should the player decide they want to do something else or approach things in an unexpected way, while a tabletop Game Master can easily change things to adapt a scenario to unexpected player decisions. While such improvisational adaptations might share elements of illusionism, they generally result in players feeling more connected to the setting and events then if the GM had simply run events as initially expected.
|Ogre art from the 1st Edition Monster Manual|
So essentially the danger with illusionism is that players will feel their actions and desires are meaningless, advancing a plot that the GM has already designed even when they want to take the game in another direction, and the advantage of it is that it can create more dramatic or responsive reactions to player decisions and character plans, goals and personalities. In dungeon crawls the advantages of illusionism rarely outweigh the risks - because the nature of the setting already contains a great many logical, diegetic (that is resulting from the story itself) restrictions on player choice. Many classic types of Illusionism are also more dangerous for the GM to use in a dungeon crawl because the sorts of decisions, especially decisions about character movement and encounters, that it tends to effect are ones that are already a focus of player attention in a dungeon crawl. For players to accept the GM violating the assumed nature of the setting: time, physics and other constants (for example putting the same mundane creature in multiple places at the same time to force a player encounter) it's best that these interventions are secret, unknown and relatively unimportant.
An alternative way of viewing illusionism is as a sort of inverse of ‘simulationism’ - the impulse to make your game as realistic as possible - entirely controlled by realistically modeled rules and chance. In the perfect (and entirely impossible) simulationist game the GM wouldn’t make any decisions, only consult rules and tables of chance and likelihood for even the most mundane events. As much as illusionism’s bad reputation is earned when GM’s use it excessively or clumsily to negate player decisions, simulationism deserves an equally bad reputation when ‘realism’ and the inescapable tyranny of chance are used in ways that make game boring or lead to frustratingly pointless character deaths (such as a GM who claims that characters have a 1 in 100 chance of slipping on tavern stairs or choking to death on a beer).