I'd be interested in answering that question as well, as I am working on a system in which cybernetic implants would be a thing, and I wonder how to deal with them. I think both ask for systematically similar solutions. So here are my thoughts on the subject:
DISCLAIMER : Not only is this a wall of text, this is a very « didactic sounding » wall of text. I know the tone I took here may sound patronizing or cringeworthy to some. It was obviously not the point and it turned out this way because of, you know, force of habit and stuff. I also have no idea what waterworld is about so I decided to take it as though we were designing gills for lovecraftian fishmen. Just sayin'.
Two things can be linked to a character: A move or a piece of gear. Both must be named. I think "Webbed hands, breathing neck" is a cool name that fits both gear and moves, so I'll pick that for the sake of example.
Let's first try it as a move. A move can :
-
Provide a flat bonus to a stat. Think : +1 Cool. Problem: I can't see any stat that this would reasonably add a flat bonus to.
-
Provide a conditional bonus to a stat (Not something that really exists in apocalypse world I think). You'd have something like:
"
Webbed hands, breathing neck: Whenever you are in the water you reveal the extent of your weirdness and get +1 Cool. This bonus goes away once you get on solid ground".
Problem: Once more, can't see the stat that this would give a bonus to.
-
Provide a conditional +1 forward or +1 ongoing. "
Webbed hands, breathing neck: Whenever you are in the water you reveal the extent of your weirdness and may take +1 forward/ongoing. You loose the +1 forward once on solid ground (+1 forward text only)".
This starts looking like something that is usable.
Problem: The +1 forward/ongoing applies to anything and everything, including, for example, « open your brain ». This I think is actually fairly cool in a « the water is my home » kinda way. But you may desire to avoid it. Also note that +1 Forward requires one more line of text (Stop condition) and is, as a result, slightly more awkward. However it also is considerably less « powerful » than the +1 ongoing.
- Change circumstances directly. Think « Acting under fire ». These types of move must have fairly specific activators and outcomes, and tend to be the longest and hardest to develop in my opinion. An example of what this may look like :
"
Webbed hands, breathing neck: Whenever you are in the water and
you need to reveal the extent of your weirdness roll +Cool. On a 10+, choose 2. On a, 7-9 choose 1 :
- You get to your destination, fast.
- You get a hold of something and bring it back to the surface, unscathed
- You make sure something stays under the waves, for good.
- You do not draw unwanted attention
These type of moves are the heart and souls of Apocalypse World and, besides making the players feel cool as heck (Which is a big deal), they drive the conversation forward by inviting the G.M to make new moves on a 7-9 or 6-.
Problem : That's a bit specific for my liking, clearly having gills and webbed hands has tons of implications, and these type of moves are more about « What would characters with gills and webbed hands can do that is cool? » and maybe not about « That character has gills and webbed hands, what does this imply ? »
- Substitute or invoke another move. You may decide that having gills affect how some other moves behave. The most obvious culprit here is « Do something under fire ». Our move may look like this :
"
Webbed hands, breathing neck: Whenever you are in the water and
you do something under fire you may
reveal the extent of your weirdness and treat the result as a 10+.
Or like this :
"
Webbed hands, breathing neck: Whenever you are in the water you reveal the extent of your weirdness and you may do something under fire without triggering the move.
Problem : This move is slightly awkward (Especially the first version) and is a « stick in the cogs » for one of the most important apocalypse world mechanics.
As a final note on moves : You may make them as complex as you like by just combining some of them together. I think a good candidate for that move would be a combination of a substitution move and a circumstance move. Example :
"
Webbed hands, breathing neck: Whenever you are in the water and
you do something under fire (or seize by force?) you may choose not to trigger the move and instead
reveal the extent of your weirdness. Roll +Cool. On a 10+, choose 3. On a, 7-9 choose 2 :
- You get to your destination, fast.
- You get a hold of something and bring it back to the surface, unscathed
- You make sure something stays under the waves, for good.
- You do not draw unwanted attention.
- You do not get hurt.
This move obviously needs more polish and playtest though. I am sure it doesn't properly covers what « do something under fire » covers, or that it is an interesting move to even have in the state it is in.
Another interesting option for that type of stuff is to make it gear. All gear has tags that can be activated by the G.M by one of his moves, which makes it cool game-wise. For example you can get it a « weird » tag, which would allow you to introduce interesting social situations. Gear is also mostly acquired at character creation and you may prevent later gear acquisition with tags that have more than one meaning. This kind of makes gear perfect for what you are trying to do. Example :
- Webbed hands, breathing neck (Organ/Implant, weird, birthright)
Now what can gear do ?
- Modify or invoke moves. They can modify their activators for example. Think « violation glove ». In this way they are very much like moves themselves. Actually we can recreate some of the previous moves by making them gear, without changing much :
Examples :
- Webbed hands, breathing neck (Organ/Implant, weird, birthright): You have+1 ongoing while underwater.
- Webbed hands, breathing neck (Organ/Implant, weird, birthright): While underwater, you may do something under fire without triggering the move.
Problem : Same as the moves these pieces of gear « copy ».
- Affect fictional positioning. Gear in dungeon world works, in the words of the creators, not to modify moves, but to allow you to make moves. For example you may have the « stone of Alambrah » and use it to roll a « hack and slash » against a magical invincible golem. Note : You would not have been able to roll the hack and slash without the stone. In this sense they have no « direct mechanical effect » and only affect fictional positioning, which is used to make moves work in PbtA games. How is it relevant for us ? Because gills could be understood as « allowing you to make moves » where others couldn't. Consider someone seeing a small boat escape. If they didn't have gills they couldn't even try to do something under fire to catch up with it. Same thing if you wanted to escape a shark by swimming, or stay in the water for 15 minutes. These objects, to work, must have a definition that gives a fairly clear idea to the player of « what they can do » in the fiction. A such that piece of gear could look like this :
- Webbed hands, breathing neck (Organ/Implanted, weird, birthright): You can swim faster, go deeper and hold your breath longer than others. You fucking abomination.
This solution is probably both the most elegant and the easiest to implement. Problem : It is also fairly « unclear » what it does, and this may trouble some players. A solution would be to « get specific » : You can swim at 12km/h and hold your breath for 60 minutes and... But this is not a very « apocalypse worldsy » thing to do.
There is a third solution, obviously, and that is making « the guy who has gills » a class in and out of itself. And this may be a fun exercise, but obviously requires a ton more work.