The Challenge of Online GamesWhat's the best way to build an endless-lifetime game, and why it's horizontal progression
There's a phenomenon that I personally find super interesting - especially since my main interest in creating games is online and web-based games - and it lies in the key difference between those online games, and offline games. With something like an MMORPG, you might expect that the fundamental difference is in the size of the playerbase - but it's actually not. The M-is-for-Massive part is just a flavor, a concern of scalability of design. No, the fundamental, key difference is: content.
In virtually any genre of offline game, you go into it with a very clear-cut expectations: the game will have a beginning, a middle, and an end. You will play the game and, if it's fun, you will finish the game. There's even the whole concept of replayable - how fun is it to start the game again, play it through, and finish it a second time? It might even be a third, fourth, dozenth time. But every time, you're essentially playing through the same game. The content that is in the game is a fixed quantity, held within the game from the moment you first open it up.
And that is where online games are different. Online games are expected to never end. You can play them for a theoretical concept of forever. And when you've got a game that you're supposed to be able to play forever, you can't release the game with a batch of content and go "okay here you go, here's the game, have fun" - because people will eventually reach the end. And then they'll complain that there's nothing left to do, because it's an online game, and the only acceptable ending for an online game is if it shuts down.
Every online game faces this issue sooner or later. And most of them, especially the RPG-style ones, attempt to solve it in the same basic way: they add more "end-game content". They take the existing linear progression track, pick up the finish line, and put it back down another mile down the road.
If you've ever played an MMORPG or a classic MUD or anything along those lines where the primary progression track is your character's level, and your level determines how powerful you are, and new content means more stuff at or beyond the max level, then you know exactly where I am going with this, and why it is a less than ideal solution.
Two words: power creep.
The further you stretch out a linear progression track, the less relevant the first part gets. You lose more and more replay value - and even worse, you start losing initial play value. Being a new player in a game full of superpowered Infinity-Level characters who can casually solo early game challenges without even trying and knowing that you can never catch up because they will just keep getting more powerful as time goes on is a really shitty feeling!
Enter the concept of horizontal progression.
The core concept of horizontal progression is simple: instead of progression meaning "getting better at doing one thing", it means "getting more things you can do".
Most games with progression are mostly linear progression, but it's very common for even those linear progression tracks to have some element of horizontal progression to them. For example, in a skill or tech tree where you can pursue multiple branches, those branches are a form of horizontal progression. However. If you have to choose one of those branches? It's not, it's just linear.
So why does this work so well for the Infinite Lifespan of Online Games, and how does it actually look in practice? To put it simply: instead of doing harder versions of the same mechanics, you get to do actually new mechanics. They don't need to be revolutionary or change the fundamental design concepts of the game or anything, but it brings in new, parallel gameplay elements. So your original content is still just as relevant and retains exactly the same amount of first-play/replay value it had to begin with, plus, your new content gets to have its own first-play/replay value in tandem. And thus, you extended the playtime value of your game! Without losing anything!
As for what it looks like: usually, it's not purely horizontal. Super Auto Pets releasing new pet packs is the only example of genuinely horizontal content releases, and that game... doesn't really have progression, so it's a pretty weak example.
Guild Wars 2, which I've been playing for years, set a policy on its original release of setting an initial level cap and never raising it, explicitly going against the (standard at the time) infinite level/gear grind. What they did instead is that each expansion added a new set of unlockable meta-abilities - like mounts - and a new specialization (build option) for your profession (class).
Note: The developers semi-recently realized that designing, balancing, and releasing a new specialization for each class in each expac isn't sustainable with their budget, so they've wrapped that up with the ones they have and are focusing on doing more widely-applicable masteries instead. It's a good case study for how to learn from your dev decisions in an active game, I think!
And then, in a theoretical game more like what I'm doing... maybe you add a new crafting profession! If you launched with Cooking and Woodworking, you could release a Tailoring Update. Or you could add a new Pets mechanic (if you don't have one to begin with).
Oooooor.... For the thought that prompted me to write this blog post in the first place.... You could have an entire magic progression system where, instead of advancing in it like a normal skill, you can gain alternate flavors of the other mechanics. And then you can release new magical styles over time so that, instead of simply adding more and more options of skills and activities, they add new layers of replay value to the existing systems.
I have only just begun workshopping that concept, but I am extremely excited about it and think it has a lot of promise, so I guarantee I'll be writing about it again!