Input-Output Randomness (Part 2)
Combining input and output randomness
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This is Part 2 of a two part series on input and output randomness. Be sure to read Part 1.
Today, let’s look at how we might combine input and output randomness.
A quick summary before we get started:
Input Randomness: The random element is introduced before the player makes a decision. For example, the player draws unit activation tokens from a bag and then decides how to move their units.
Output Randomness: The random element is introduced after the player makes a decision. For example, the player decides to attack a skeleton and then rolls dice to see if they hit.
Input vs. Output Randomness
It’s a common idea that input randomness (prevalent in modern Eurogames) is superior to output randomness. I’m not so sure that’s always true. Strategic wargames, skirmish games, and many TTRPGs rely heavily on output randomness, and can be a lot of fun!
I think it’s better to consider both input and output randomness as tools in a toolbox. Knowing when to use each is the key. Or perhaps combine them…
I recently read a paper called Effect of Input-Output Randomness on Gameplay Satisfaction in Collectible Card Games.
In it the authors explore which types of randomness provide for the best player experience in a game. They even went so far as to design an an entire online CCG just to test their hypothesis. It’s a fascinating paper, and I suggest you read the whole thing!
So what is input-output randomness? Here’s how they define it:
Input output randomness is a cornerstone of collectable card games like Hearthstone, in which cards are drawn randomly (input randomness) and have random effects when played (output randomness).
You draw cards (input randomness) and then decide which to play and how to use them (player decision). The final result of some attacks, however, is determined by elements of randomness (output randomness).
For example, you might use Pawniard’s Triple Cutter attack. This is resolved as: “Flip 3 coins. This attack does 10 damage for each heads.” You decided to use the attack, but the actual damage output is somewhere between 0 and 30!
Input-Output in other games
Two games immediately come to mind when thinking about input-output randomness, both of them are designed by David Thompson:
For What Remains (Thompson, et al., 2020) relies on both types of randomness to create a satisfying player experience. The player controls which unit tokens are added to the bag, and then luck determines which units get activated. The player decides how to move and use their activated units, but combat results are ultimately determined by dice rolls.
In Undaunted: Normandy (Thompson & Benjamin, 2019) players build their deck over the course of the game, drawing cards from it each round. They choose which cards to play and how to use them. Again, however, combat is ultimately determined by luck of the dice.
Applying this concept to TTRPGs
I often wonder how these concepts could be applied in different genres of games.
Many (though not all) TTRPGs that have combat rely on output randomness. You decide to attempt an action, add dice to your pool or count your modifiers, and then chance will determine if you were successful or not. We looked at this in the Peggy Steals an Artifact and Upside Down Fairytales posts.
Switching to input randomness might add more player agency. Rather than rolling to hit, perhaps you draw cards or have rolled your dice ahead of time. Gloomhaven (Childres, 2017) is probably a good example of this.
The catch or potential downside, however, is that adding more player agency and decisions can slow a game down. AP can set in, making some players take particularly long turns. If the mechanisms are too detached from the game, it can pull players out of their immersion, breaking the magic of roleplaying.
Some things to think about:
Input vs. Output: Don’t consider them as opposing styles. Both input and output randomness can be used to create engaging and exciting player experiences.
Combine types: Although players have different preferences, I personally enjoy a little output randomness thrown into the mix. Particularly in wargames or area control games, it’s OK to get a horrible roll and lose a battle. It’s less OK, however, to lose the game due to just bad luck.
Input-Output TTRPGs: Input-output randomness is easy to implement in TTRPGs, but probably hard to implement it well. Consider how mechanisms relate to the theme and immersion of roleplaying games. Too much and it might feel like a board game.
This week’s poll asks how you like your randomness in TTRPGs. Do you want input randomness (e.g. draw cards and then make your decisions) or output randomness (e.g. attack and roll the dice)?
See you next week!
— E.P. 💀
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