Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Practical Techniques for Implementing Emergent Gameplay Would the Real Emergent Gameplay Please Stand Up? Randy Smith Harvey Smith

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Intro Harvey Smith—Deus Ex/Invisible War Randy Smith—Thief 1/2/3 Ion Storm aesthetic goals  Improvisational (player-authored) gameplay  Benefits from large gameplay possibility space  Emergence provides more explorable space

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Our Topic How to Add Meaningful Emergence to Video Games Topics that have been covered elsewhere:  History of Emergence  Emergence and Narrative  Emergence and Uncertainty  Benefits and Costs/Risks of Emergence

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Focus Less Theoretical, More Practical  Related to modern game system design  Skewed toward large-scale action games Emergence within a game system context  No player psychology, social influence, etc.  Focus on the system space of game –Power-ups, Weapons, Tools, Monsters

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Disclaimers Emergent gameplay isn't necessary to design good games No holy wars, despite the provocative title of the presentation

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Takeaway A practical approach to creating meaningful emergence in your own game designs. You are a game designer  You design game systems  You want to focus on emergent gameplay  How do you accomplish this?

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Outline Preamble Intro to Emergence Creating Emergence –Creating Mechanics that result in emergent game dynamics Qualifying Emergence –Creating emergent gameplay that results in meaningful game aesthetics Wrapping Up Q & A

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) I – Intro to Emergence Definitions Vocabulary Examples

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) A Typical Real-World Definition A discernable, higher-level behavior of a system which is not immediately obvious by looking at the low-level rules that govern the system’s behavior. …let’s look at an example of real- world emergence

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Global Warming

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Global Warming

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Global Warming

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Global Warming

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Global Warming

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) MDA Framework A rules-oriented approach to game design Mechanics—The rules of the game Dynamics—Real-time rules interactions Aesthetics—Human emotional responses

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Emergence in Video Games (our definition) A second order game Dynamic created by the interaction of first order game Mechanics.

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Example 01: GTA3 Player accidentally flips his car, which explodes, injuring nearby pedestrians who begin to attack him  Player takes a jump   Car flips and lands upside down   Car explodes   Nearby pedestrians are injured by explosion   Pedestrians begin to attack player

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Example 01: GTA3 Player accidentally flips his car, which explodes, injuring nearby pedestrians who begin to attack him  Player takes a jump   Car flips and lands upside down   Car explodes   Nearby pedestrians are injured by explosion   Pedestrians begin to attack player Note that there is no explicit Mechanic describing this behavior

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Example 02: Tactical Shooter Indirectly Connected game Mechanics  Gas barrels Leak poison when ruptured  Poison Kills enemies and players  Bullets Kill enemies, and Rupture gas barrels  Weapons Fire bullets when dropped  Enemies Fire bullets, and Drop weapons on death Player shoots guard  guard drops gun  gun goes off when it hits the ground  bullets rupture barrel  poison leaks out  poison kills other enemies

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Example 03: Thief In order to injure a nearby guard, player ignites an oil puddle by knocking a candle off a table  Player throws a box at a table   Table wobbles   Candle falls off table   Candle falls into oil puddle   Oil puddle ignites   Nearby guard is injured by the flames

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) MDA Framework

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) MDA Applied to Emergence Mechanics  The rules of the game  You modify Mechanics to alter emergent interactions Dynamics  Real-time interactions between Mechanics  Mechanics connecting to each other  Where emergence happens Aesthetics  Human emotional responses  Wider exploration space, emergent narrative

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) II – Creating Emergence Quantitative Mechanics Connecting Mechanics Together Relevant Technology Populating the world with Mechanics

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Where Mechanics “Live” Power-ups  “When guns hit the ground, they fire off bullets” Environmental Objects  “When barrels are damaged, they release poison gas” Simulations  “Cars can flip upside down when they land from jumps” Autonomous Agents  “If pedestrians take damage, they attack whoever is responsible” Etc.

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) more about Autonomous Agents  Can act independently, possibly react dynamically to situations  Guard AIs in Deus Ex and Thief  Cars and Pedestrians in GTA3  The Bat in Adventure  Special properties  Emergence without direct player intervention  Make the world feel alive  Create dynamic situations

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Creating Emergence by Adding Indirect Connections Emergence fails to happen when Mechanics aren’t indirectly connected Emergence can be created by adding more indirect connections – making the Mechanics “listen to” each other  Guard with torch slips on oil puddle   Guard falls to the ground  Nothing else happens

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Creating Emergence by Adding Indirect Connections Emergence fails to happen when Mechanics aren’t connected Emergence can be created by adding more connections – making the Mechanics “listen to” each other  Guard with torch slips on oil puddle   Guard falls to the ground   Guard drops torch   Torch ignites oil puddle …let’s talk more about connecting Mechanics

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) The Tactical Shooter Example Indirectly Connected Game Mechanics  Gas barrels leak poison when ruptured  Poison kills enemies  Bullets Kill enemies, and Rupture gas barrels  Weapons Fire bullets when dropped  Enemies Fire bullets, and Drop weapons on death

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Visualizing All Mechanics

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) -1 Mechanic

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) -2 Mechanics

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Getting Mechanics to Connect Again, it helps to have a rules oriented approach It’s tempting to spam the world with Mechanics, to pile them on Mechanics are independent, but indirectly connected Some Mechanics are more highly connected How do you get the best return on your investment? Choose Mechanics that have relationships to each other

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Example from DX:IW: Choosing Where to Invest Prismatic Resonator Biomod  Fewer Indirect Connections –Beam Triggers (3 types) Bot Domination Biomod  More Indirect Connections –All robots (8 types), Cameras, Turrets, Spiderbombs  Bots are improvisationally useful for combat, door opening, setting traps, etc –Players started using spiderbombs to open doors

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Player Improvisation Players ‘Unlocked’ Doors with Spiderbombs Indirectly Connected Game Mechanics  Spiderbombs –Spawn Spiderbots  Spiderbots –Obey All Bot Rules Susceptible to Bot Domination Susceptible to EMP Explode If Damaged Post-EMP  Bot Domination –Possess Bots –EMP Bots Post-Ejection  Doors –Can Be Locked/Lockpicked –Destroyed By Explosions

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Player Improvisation

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Invest in Related Mechanics If you’ve already got these Mechanics:  Flamethrower can catch enemies on fire  Burning enemies can catch furniture on fire Add more elements and Mechanics having to do with fire, e.g.:  Fire extinguishers  Oil puddles  Dynamite  Candles  Water arrows

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Supporting Technology Takeaways  Some technology supports the implementation of emergence better than others  Need to work with technologists to evaluate your technology status

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Supporting Technology Explicitly hard-coded Mechanics are messy and difficult to support You might forget to implement one of them

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Supporting Technology The Stimulus System is a generalized way for objects to listen to each other You can describe objects intuitively

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Supporting Technology Easier to create and modify connected Mechanics More reliable and likely to create improvisational emergence

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Ion Storm’s Supporting Technology Stimulus System  Generalized channel for objects to listen to each other  Don’t have to explicitly hard-code Mechanics Property System & Object Hierarchy  Quick and easy creation and editing of objects Scripting System  Quick and easy to describe resulting behaviors  Oil puddle: “When I receive fire stim, turn into a fire puddle”

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Populating the world with Mechanics For Mechanics to connect, they typically have to exist in physical proximity to each other.  How rich is your world with Mechanics? E.g. – how many gas barrels exist in your world?  How often are the connected Mechanics in proximity to each other? E.g. – do you ever place guards near gas barrels?

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Examples of World Population from Thief Negative example  Fire elementals that re-light torches when guards are nearby in Thief  Good idea, but Fire elementals and Guards / Torches were never in the same levels

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Examples of World Population from Thief Positive example  Player shoots arrow at a candle to knock it over  arrow misses and hits metal door instead  nearby guard hears sound and comes to investigate  Physical surface, Sound Propagation, and Lighting house Mechanics in Thief ..and they populate the world exhaustively.  What elements already exist in your world which you can add Mechanics to?

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) III – Qualifying Emergence Qualitative Aesthetic Goals Meaningful Emergence Involving the Player

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) What are your Aesthetic Goals? What do you hope for emergence to contribute to your game?  Deus Ex = Empower many emergent solutions  Thief = Creating the occasional sublimely tense moment of emergent challenge  GTA3 = Simulate a dynamic, responsive, living world; Enable emergent mayhem  All three = Authoring your own experience (emergent narrative)

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Meaningful Emergence In accordance with aesthetic goals The player perceives the events Impact on gameplay experience, Not just some wacky outcome  No gameplay relevance: Prox mine wall climbing  Gameplay relevance: Spider bomb door unlocking Meaningful to the fantasy  Violates fantasy: Age of Empires sheep

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) How involved is the player? Does the player have input into the Mechanics which create emergence? Theoretical Game: There is a factory with lots of robots interacting emergently. If they touch you, you die, but they don’t react. Get to the other side.

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Robot Factory Game

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Player Perception of Emergent Experiences Reactive – does not require player input  “Emergent challenge” – a challenging situation that develops emergently  E.g. – the previous robot factory example  E.g. – pedestrians in GTA3 turn hostile toward the player

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Player Perception of Emergent Experiences Proactive – player must provide input  “Emergent solution” or “Emergent strategy” – the player creates their own solution to a problem by leveraging their understanding of the game’s emergence  E.g. – igniting oil puddles by knocking a candle off a table in Thief  E.g. – player runs over pedestrian to summon ambulance for ambulance missions in GTA3

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) IV – Wrapping Up Design Process References

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Emergent Gameplay Design Process Aesthetic Goals  Widening possibility space via emergent systems Technology Considerations Plan Game Systems  Player agent(s), tools, traps, resources, etc.  Decide where to invest, Disregard low connection Mechanics Populate world with Mechanics Evaluate system Dynamics  Quantitatively –Litmus test—2 nd order consequence? –Common enough? –Perceptible?  Qualitatively –Dynamics match the fantasy? –Did you meet your aesthetic goals? Iterate

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) References Various References to Emergence  Marc LeBlanc’s GDC Lectures Rules of Play  Book by Eric Zimmerman and Katie Salen Dynamics for Designers  Will Wright’s 2003 GDC Lecture Complexification  Book by John L. Casti Emergence  Book by Steven Johnson

Practical Techniques for Implementing Emergent Gameplay (Would the Real Emergent Gameplay Please Stand Up?) Practical Techniques for Implementing Emergent Gameplay Randy Smith Harvey Smith Q & A