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swimming & oceanwalking
Swimming does not work in the same manner as it does, on the real world. On the mana world, the only place where one can swim, is where the water meets air. Any level of swimming ability probably determines how fast you're able to move across this top layer of airy water. You can only swim on the surface of the water and can not simply sink, or dive downward to access the ocean floor; No Z-axis.
However, if you have gills or some other method of waterbreathing, you can walk safely on the ocean floor. As stated, this can not be accomplished by sinking or diving, since the layer of airy water can not be penetrated. The only common places to access the ocean floor, are beaches. Beaches serve as ramps to and from the ocean floor. There probably aren't very many access points to the ocean floor.
With this contrast between swimming and oceanwalking, we can allow people to swim without ever having to depict under-water swimming. (which would require more sprite frames) Swimming can be portrayed as simply as it is in other 2d games, like Zelda and Graal.. where the character's head is (partially) above water, with some simple splashing graphics and sounds to assist the illusion.
Under-water travel on the other hand, could be done fairly exactly as it's done in the SNES title "Breath of Fire".. a method of which I am very fond.
elements and materials
I've been trying to come up with a material tree, based on three fundamentals: The fantasy-style elements that we've adopted, the real-life table of elements and of course, as the governing guideline, the rule of cool. Unfortunately, I was once again unable to come up with a complete idea on my own, but this is the gist of it.
energy to matter
Using the following forces, elemental energy can be converted in to various types of matter.
- fire = heat
- lightning = electricity
- air = gas? wind?
- ice = cold
- water = moisture
- plant = acid
- earth = pressure
- metal = magnetics? gauss?
These could be some of the basic forms of matter that we're able to create from elemental energy. Metal is the only complete set amongst these examples.
- sulfer (heat), lithium (elec), silicon (pressure), carbon (magnet)
- iron (heat), aluminum (elec), titanium (gas), cobalt (cold), tin (moisture), zinc (acid), lead (pressure), nickel (magnet)
Aside from the potential to be blended in to alloys, each type of metal could have various forms of modification applied to them. (hardened, tempered, galvanized, etc..)
- nitrogen (cold), hydrogen (moisture), xenon (acid)
obviously, it's a little easier to do with Metal than the others. I imagined this might somehow lead to a the development of a metal / alloy-tree, that would actually have some sort of function beyond sounding cool. Another purpose was to provide a foundation for at least some level of familiarity. For example, it's fairly common knowledge that steel is usually made from a mixture of iron and carbon; wouldn't it be cool if that mixture actually resulted in a steel product, when you tried it in-game? It would definitely take some discussion to make it usable, but I would love to see a material tree developed beyond a generic list of things like, "ore, wood, blah blah blah.."
Another piece of the idea was to reference historical alchemy. The above mentioned metals could be basic forms of the precious metals. Iron could be turned in to Gold, while titanium could be turned in to Silver. Aluminum (being relative to electricity which is between Silver and Gold) could be turned in to Electrum. If we did this, an imbalance in currency value could be avoided, by using fiat currency in all civilized areas. Precious metals might then be reduced to a value more relative to their usable qualities.