Replayability is a buzzword in the industry, but it generally is referring to how good a game holds up after multiple playthroughs. It is assumed to be just a proxy of how good a game’s design is, but that isn’t necessarily true: games have to explicitly tailor mechanics a certain way in order to optimize replayability. Replayability isn’t always something to prioritize over everything else - cohesive, story-driven games, or contained experiences, often prefer presentation and clear progression - but in games with more emergent narratives, it is a very important virtue to pursue.
Thrive, of course, is a sandbox game with emergent gameplay. So replayability is very important to get right.
What Creates Replayability?
At the most abstract level, there are essentially three big ways of introducing replayability:
- More Content/Mechanics - Introducing more for the player to potentially encounter. When well done, mechanics naturally work with other mechanics, and provide the player with a lot more variety. When poorly done, additional features are grindy, add excessive bloat, or offer “false-choice dilemmas”: situations where different choices aren’t as different as they seem, or offer little variety.
Content obviously reflects everything related to a game’s scope, but common examples of additional content and mechanics include side quests, providing numerous abilities, and RPG/strategy yields.
- Constraints - Sectioning off parts of the experience so that players cannot possibly experiment with every single mechanic available in the game. When well done, constraints allow players to focus on optimizing their current path. When poorly done, constraints seem arbitrary to the player, are tedious, or act as impediments to what a player wants to do.
Common examples of constraints include defined archetypes and unlock conditions, as well as branching paths.
- Randomness - Introducing variety to existing content so that players don’t always experience identical playthroughs, even if similar strategies are taken. When well done, players are provided a chance to mix up their gameplay. When poorly executed, players aren’t able to form any strategy, and gameplay is too volatile to experience the full depth of mechanics offered.
Common examples of randomness include procedural generation and events/decisions in strategy games.
It should be noted that both constraints and randomness are inherently involved in content and mechanics. However, constraints represent guidelines sectioning off content, while randomness serves as a means of providing variety to existing content.
Adding Content & Marginal Utility
As a game fills out, the marginal benefit gained from adding more mechanics starts decreasing, largely defined by the cost of the time spent pursuing one piece of content over another. Where an incomplete game generally benefits from whatever content it can get, a more fleshed-out product does not benefit as much, requiring a more selective process in determining what to work on. Here are common faults of games which overly rely on adding more content to improve replayability.
More of the Same
As a general rule, adding a different variety of what already exists quickly becomes less worthwhile as more of said content is present in a game. If Skyrim had 30 different one-handed weapons and only 4 different bows, it would make much more sense to focus on adding more bows than it would adding more one-handed weapons.
In Thrive, This is a primary reason why I am wary of adding different patch types. Though different environments do ideally provide different contexts for the use of different abilities and tendencies, the way Thrive is right now results in environments being little more than varying backgrounds, and some volatility in compounds. Prioritizing mechanics which provide us with an ability to further distinguish existing patches is currently much more valuable than adding more patches.
A similar issue also exists with adding additional metabolisms. Currently, adding different metabolisms will likely result in the addition of another cloud, or additional chunks to consume.
Situationality
This isn’t as hard of a rule as the above, but it is generally better to implement mechanics that have more general impacts on the gameplay experience rather than concepts targeting very specific niches.
This isn’t to say that there shouldn’t be special handling of different archetypes. Rather, the takeaway is that variety across different archetypes should ideally be introduced through dynamism in a mechanic that exists across all builds, rather than a handful of extremely tailored and distinct mechanics targeting each individual build.
Take Kerbal Space Program for example. The crux of its replayability isn’t guaranteed by the various tools provided to the player, but instead, from the overarching mechanics the player must always face - particularly, those mechanics related to aerodynamics. The fun part of Kerbal Space Program isn’t sending a rocket to space and pressing a button to activate an ability: it’s creating a structure with those abilities, while ensuring it has a proper center of mass, while ensuring it is aerodynamic, and the differences in gameplay resulting from variety to aerodynamism.
Such would also be true in Thrive. Adding a tailored mechanic to only organisms with a chloroplast would be cool, say for example, introducing an optimal color depending on the characteristics of your star to conduct photosynthesis. However, adding a system affecting all organisms - tracking their tolerance to sunlight for example - offers a lot more value to the game, providing more replayability for players across different environmental ranges.
Assessing Thrive’s Replayability
First, let’s discuss context. In many ways, Thrive is guaranteed more replayability than most games due to its procedural nature. Even for a game that hasn’t been fully fleshed out, a disproportionate amount of replayability is conferred due particularly to auto-evo. As auto-evo matures, and as similar methods of dynamism are introduced to the environment, replayability will inherently be offered no matter how much additional content is added. That is testament to a solid gameplay foundation to the stage.
Another thing I want to bring up is the fact that the Microbe Stage represents a simple stage of Thrive, and as such, the “reach” of replayability is not bound to a single stage. Part of this is to say that replayability will inherently be introduced as more of the game gets developed. But another part is that our concepts must be aware of the fact that the goals of our replayability extends to beyond the stage. It is okay if we make decisions not to enhance the replayability of the Microbe Stage, as we need to consider the game as a whole.
Going off content related to the roadmap, I’d say Thrive has an adequate amount of content, an insufficient number of constraints, and a good, but hampered, level of randomness. I will judge current gameplay below and current plans for road map items, as it is impossible to predict how exactly future concepts will be implemented after constraints are considered.
Thrive’s Content
Strengths
These represent content areas that we have a sufficient level of content in.
- Though the book isn’t necessarily slammed shut, the number of compounds present in Thrive represents a good variety of metabolisms. We represent autotrophy, organotrophy, chemolithotrophy, and various combinations of resulting diets. If more content is to be added here, I would recommend improving our anaerobic metabolic processes.
- A good number of abilities are represented in Thrive, representing defensive abilities, movement-related abilities, and projectile-related abilities among others. More unique abilities are always welcome to be implemented, and concepts exist for them (Comprehensive Combat Revamp - #12 by Kashnox), but this isn’t an area of the game that is actively holding us back.
Weaknesses
These represent content areas where we don’t genuinely offer much choice and variety in which I think are holding us back a bit.
- Patches currently offer very little variety besides introducing different compound levels. Introducing dynamic environments will help, but the inherent experience of specific patches would still be very similar. Introducing currents and terrain will help with this immensely, and they should be prioritized.
- Membranes don’t offer enough individualized differences. Balancing could help, but a big part of the issue is that engulfment is just too powerful of a tool to justify not very visible stats. It might be worthwhile to revisit the shield mechanic.
- Three different compounds (iron, glucose, and sulfur) don’t offer much difference to gameplay besides targeting different colored clouds. The solution isn’t necessarily different mechanics for the different metabolic strategies related to them, but could instead be introduced through having different stats be more important for different metabolic strategies.
Thrive’s Constraints
Strengths
These are mechanics which do a good job of restricting bloated/spongy playstyles from the player.
- Unlock conditions don’t immediately open up the entire tool box to the player, which has done wonderful things for progression. Endosymbiosis is also a very clever way of integrating scientific theory with an engaging unlocking mechanic.
Weaknesses
These are areas of the game which aren’t balanced in a way which incentivizes specialization from the player.
- Currently, there is nothing penalizing players from gathering as many parts as they want, or generally increasing the size of their organism. As a result, players receive no penalty for hoarding parts, and aren’t incentivized to specialize. Introducing size-related costs could be a direct address to this.
- There aren’t many challenges the player faces in shifting strategies besides the lack or presence of given metabolic parts. Player’s absolutely shouldn’t be locked in on a path, especially early in the game; however, not having aspects of this challenge harms replayability, as there is very little stopping the player from literally placing whatever they want. In other words, “archetypes” are weakly enforced.
- There is very little restriction on movement currently in Thrive. This will be aided dramatically by the inclusion of environmental tolerances.
Thrive’s Randomness
Strengths
These represent areas of the game which do good in bolstering a diversity in potential encounters and situations.
- Auto-Evo can consistently generate some very unique and interesting organisms, inherently bolstering Thrive’s replayability.
- The patch map is a great way to offer some sort of variety in the player’s journey. Once patches are made to be more distinct, randomness will be bolstered.
Weaknesses
These represent areas of the game which impede the amount of randomness offered to the player.
- Environments are rather static, though this has been and will continue to improve throughout 0.8.
- Auto-Evo and the AI neglect various abilities, such as mucocysts, the variety of toxins, jets, and various membranes. There also tend to be few natural predators of the player.
What Are Some Potential Solutions?
First, an all-encompassing consideration: the AI of Thrive desperately needs attention. Improving CPU behavior will offer a lot more engaging gameplay, which will boost existing mechanics dramatically. Improvements to auto-evo will also universally benefit the game’s experience, but that isn’t necessarily something that is desolate - more so, it’s something that inherently requires continuous refinement.
Content
- Membrane Balancing - Balancing membranes in a way to encourage branching out from single/double membranes would be an easy way to offer more build diversity. A slight tweak of the injecting pilus might be necessary, as it should inherently bypass all toxin immunity offered by an external membrane.
- Currents Revamp and Terrain - Actually implementing currents, and introducing some way for the player to increase or decrease their effect on the organism, could offer both direct differences across different patches and a very nice effect on movement adaptations. The same goes for terrain.
- Completing Siderophore Implementation - Siderophores currently need an AI addition, but functionality is currently implemented. Once implemented, balancing of iron chunks can begin to offer iron-dependent gameplay a cool dynamic.
Constraints
- Buckly’s Progression Revamp Concept (Re-assessing Microbe Stage Progression: The Proteome Method): A nice way to address specialization, where MP discounts are applied depending on the prior existence of a part on your organism. Also provides some constraint on size.
- Surface Area to Volume Ratios (Surface Area, Volume, and Ratios - #37 by Deus): This would be a nice way to introduce stats which enhance the strategic depth of creating an organism.
- Size-Related Costs (Size & Osmoregulation): Introducing this will force players to be more concise about what it is they are placing down on their cell, as well as require greater adaptive specialization to become big rather than size-increase being an inherent function of progression.
Randomness
- Auto-Evo Refinements: This is an on-going process, but making it so that auto-evo is able to evolve some of Thrive’s more unique abilities, such as the mucocyst and slime jets, will allow for more variety in organisms. Adjusting the distribution of organisms to create organisms that pose more of a threat to the player is also a goal, though this is related to AI refinements as well.
Takeaway Assessment of Microbe Stage Replayability
Ultimately, I feel confident saying this: I do think the Microbe Stage could be somewhat lacking in replayability upon completion of the roadmap, but not in a manner that is far off. In other words, we’d end up with an adequately replayable game, and then with a few tweaks, we could really maximize replayability. Clever balancing tweaks could take us halfway to an ideal level of replayability. Most of what is needed is already there; consideration of how to enhance constraints and progression to ensure specialization is a very important thing to keep in mind.
I do think we should consider adding a few mechanics to the Microscopic portion of Thrive, BUT we should only make up our mind on those additions when we are developing the Multicellular Stage. That way, we can consider what design choices are necessary for Thrive’s next phase of development. I already assume we’d need to somewhat rebalance certain things to make the Multicellular Stage more polished, so it might be best to consider that then.
In the meantime: to any volunteer programmers reading this looking for new things to try out, I have linked relevant threads in the above section. Please let me know if any of these features stick out to you, and I can give certain concepts a look over and give you some relevant information.