Uncertainty in Legacy Games

Uncertainty in Legacy Games

15 July 2025

Greg Costikyan's 2013 book Uncertainty in Games [1] has been an amazing tool for me as a game designer. It is a deep dive into the concept of "uncertainty", or anything in games that makes it so the player cannot fully know what will happen next. Costikyan argues that uncertainty is crucial to keeping games interesting, and lists many different ways that games can be uncertain, from tests of physical ability to randomness. The book touches on digital and tabletop games, from Mario to Chess to Magic: the Gathering, but one thing Costikyan doesn't mention is the tabletop genre of legacy games.

Legacy games are notable for permanently changing over their lifetime. Boards get covered in stickers and cards get torn up so that each playthrough is different from the last. The genre was invented by designer Rob Daviau, who said in a 2017 GDC talk [2] that the idea came from a joke about the board game Clue: "I don't know why they keep inviting these people back to dinner every night, they always kill someone!"

Daviau's first legacy game was Risk Legacy in 2011. Despite releasing two years before Uncertainty in Games, legacy games receive no mention in the book, this is likely due to the long publishing times of academic texts such as this. I want to cover three of Costikyan’s sources of uncertainty, and address how legacy games expand on them with their unique mechanics. For each source, I will describe it, discuss what Costikyan says about tabletop games in it, and then compare it to what Daviau says in his talk about legacy games.

Hidden Information

Hidden information is exactly what it sounds like: information that a player does not currently know. This could be the cards in an opponent's hand in poker, or the world beyond the fog of war in a Civilisation game. While both tabletop and video games can contain hidden information, Costikyan claims that tabletop games can only have a finite range to their hidden information. Conventional tabletop games cannot surprise players with new mechanics because everything is written in the rulebook, "the extent of the system is known and visible before play.”

This is not true for legacy games. Introducing new mechanics during or between playthroughs is a core feature of the genre. Daviau discusses the secondary objectives in Risk Legacy: when certain conditions are met (such as one player winning two games), new mechanics are introduced. He says that players ended up so curious as to what these mechanics would be, that they would willingly lose a game if it meant achieving a secondary objective. This speaks to the effectiveness of hidden information in these games, revealing just how much players are driven by curiosity.

Development Anticipation

Development anticipation is the uncertainty of what will be added to a game over time. Costikyan uses the example of World of Warcraft, which adds new quests and narrative in each major update. He also discusses the indie game trend of releasing in public beta, where players can purchase the game with the understanding that more will be added as the game is built.

Costikyan says that "until the rise of online gaming, games were largely fixed on release," and while it is still true that everything that will be in a legacy game is in the box when you purchase it, many of the mechanics are only revealed as the players progress through the campaign.

In Risk Legacy, the board develops as stickers are added to it, representing new cities being built and scars being inflicted on the landscape. And, as previously mentioned, the secondary objectives introduce new mechanics over the course of the campaign. This means that each session will begin differently to the previous one because of changes made to the board, as Daviau puts it, "Whatever they did in the last game, it's only 90% relevant to this game." This is a perfect example of development anticipation in action, with strategies changing due to mechanical additions to the game.

Narrative Anticipation

Narrative anticipation is the uncertainty of narrative, Costikyan says it is the same uncertainty that "keeps us reading a novel." He naturally discusses games with a heavy reliance on writing, such as RPGs and MMOs, but the discussion takes a curious turn as Costikyan grows more abstract in his use of the term "narrative". He includes the anticipation of new mechanics in a platformer, and even discusses Chess:

"[While playing Chess], we want to see how our opponent will react, how forces will ebb and flow over the course of play. There’s a sort of narrative arc at work here, even if there is no direct connection to story."

Pandemic Legacy, on the other hand, is a tabletop game that does have a "direct connection to story." In the GDC talk, Daviau explains how the order of cards in the deck was directly inspired by the three-act structure, creating an explicit narrative arc over the course of the campaign.

If we follow Costikyan's idea that introducing new mechanics falls under narrative anticipation, then Risk Legacy's previously mentioned secondary objectives also fit neatly here. The players know that something will be introduced when they complete this objective, but they don't know the details until it happens. There is that same expectation as in platformer games that new mechanics will be introduced to keep the game exciting.

It was a real shame that the legacy genre was just missed by Uncertainty in Games. It completely redefined how board games are understood and paved the way for plenty of innovation in legacy gaming and in the broader tabletop scene. Daviau mentions the tabletop game Fabled Fruit, which takes the concept of introducing mechanics over time from legacy games but restrains it back so that each session has a fresh start. Additionally, the 2024 game Yazeba's Bed and Breakfast takes legacy mechanics and applies them to the medium of TTRPGs, the game introduces new mechanics over time and asks players to deface their book with writing and stickers. So much can still be done in the legacy game sphere, I'm really curious to see what comes out of it in the future!

References

[1] Uncertainty in Games (2013), Greg Costikyan. Published by MIT Press.

[2] Legacy Games: From 'Risk' to 'Pandemic' to 'SeaFall' & Beyond (2017), Rob Daviau for GDC. Available at: https://www.gdcvault.com/play/1024259/Legacy-Games-From-Risk-to.