So yesterday the Multiplayer BoTW mod that Smallant put a bounty out for got released, and it got me thinking about the other online multiplayer mods or modes for games I have enjoyed recently and a style of co-op gameplay that they represent.
This style is one that I've started to call "Synchronus Co-Op", because often they are represented by modes or mods that synchronize some of the state of the game in some manner, but do not synchronize everything.
There are two examples I can think of to maybe help better describe what I mean.
The first is the homebrew "Soul Link" game-play rules for Pokemon games. These rules are a derivative of the Nuzlocke rules (you can only catch one pokemon per route, fainting = permanent death) but extended into a multiplayer setting.
The idea being that for X number of players, the pokemon they catch for a given route are "linked" and anything that affects one pokemon affects the others, e.g. if one player has a pokemon in their party all the others must have the linked pokemon in their party, and if one pokemon dies all the linked pokemon die.
This obviously isn't traditional co-op, because every player is playing their own version of the game, however as a consequence of the rules the state of one players game affects the states of the other players games.
The other example I would give is the myriad of online mods for Zelda games and combining them with Randomizers. Most of these online mods work by synchronizing the flags of the games between them (such as open chests, obtained items, etc), but otherwise are not "true" co-op (e.g. you can't fight monsters together and the whole world is not synced).
In normal Zelda, this style of co-op wouldn't be super fun, but when combined with a Randomizer is actually becomes a huge blast! Randomizers for Zelda games effectively turn the game into a giant scavenger hunt which meshes perfectly with this style of co-op. While one person can go off and check an area for treasure the other person can go to a completely different area it works wonderfully.
Now, I think its fairly straightforward why this style of online/co-op has cropped up in the mod/homebrew world for games. It's because its a lot easier to implement. As the pokemon mode shows, you can effectively implement this style of multiplayer through just home rules, and for mods like the zelda online mods, it's something that can run outside of the game itself (client/server) and modify the game through memory manipulation.
What I have been wondering recently is if this style of co-op has cropped up in games directly yet.
It feels like the sort of thing that would work really well in say a rogue-like as a way to give it a co-op twist (such as, two players delve into dungeons and the items they get share between them) while also being relatively lower cost to implement, but idk I'm just a web developer.
It would be exciting to see though, so I will hold out hope that someone might look at this style of co-op and make a real good version of it in a game or something.
Actually, this sort of thing is kind of being added in Crypt of the NecroDancer's new Synchrony DLC!
On top of just generally having reworked the entire engine from the ground up to enable good rollback netcode for online multiplayer, there's a new shrine in co-op mode called the Shrine of Binding.
The Shrine of Binding can be activated when two players bonk it simultaneously. This then forces the following on these two players:
- they share the same singular inventory, health bar, and coin multiplier
- if one takes damage, it affects the bound health pool (i.e. both are affected)
- and while bound in online multiplayer, it enforces the camera to work as if the two bound players were in a local multiplayer session (i.e. the camera will zoom out so that both players are in the frame and centered between them; if one teleports to/from a secret shop, both will appear in the shop entrance/exit rune, and I think regardless of settings, if one goes down the floor's exit stairs and the bound players are the last ones in a multiplayer session to take them, then the session gets taken to the next floor).
This DLC also enables highly customizable LUA modding far beyond what was available in the original game and Amplified DLC, to the point that if it's not already available, I'm sure a mod that forces the Shrine of Binding effect from the beginning on all players in a session wouldn't be all that hard to implement.
Granted, this would be a more typical example of direct co-op, I guess, rather than multiple sessions of the same game but only indirectly interacting with each other. Technically, I think this indirect method is also possible with the modding API, but would be slightly more complicated. However, the racing league has already done something similar for same-seed, separate world, non-interactive sessions outside of "if one racer wins, then it kicks both out to the lobby", so it probably wouldn't be too much of a stretch to utilize a lot of the same functions to achieve indirect co-op across multiple "worlds" in the fashion described in the OP.
