Thesis:
Survive and evolve. You exist in a prehistoric world with dangers lurking around every corner; your mere existence is a struggle to survive. Some days even the simple tasks of eating and drinking become the entire days work. As you go day to day the local food sources dry up; you have pick all this seasons berries, the local fish stock is over fished, and your presence has scared away most of the game animals. You survival now becomes exploration of the environment, you must find greener pastures and along the way gain knowledge and build relationships to evolve your species.
Synthesis:
As you survive day to day your interactions with the environment will gain you knowledge and understanding of the environment, survival skills and techniques, and later on building relationships. This will give you more options and choice in the game as you make the decisions on how to survive and what skills to develop to make your daily life easier and to evolve into a lasting race. This will lead to different hunting skills and weapons, formation of communities, and a unique game play scenario for each player every time.
Antithesis:
To survive you must maintain the basics of life: food, water, and sleep. These also represent your name stats in the game: Hunger, Thirst, and Energy. To eat you and forage the land to find: berries, vegetation, and mushrooms; and you can hunt: insects, fish, birds, and animals. There are several local water sources to drink from, but as you venture outward from your known world finding water can be the difference between you having offspring or your genes being wiped from the pool. The last part to the basics of survival will be to rest/sleep. You will be allowed to sleep anywhere you want, but the key will be to choose a safe place to rest. Otherwise you may find natural selection knocking at your door as the night gives new challenges to your existence.
To maintain Hunger you have to eat. You can do this by interacting with vegetation, berry bushes and fruit trees, and by hunting animals in the environment. To hunt anything but insects you must have a spear that you can fashion from the environment; more on the spear later. This is key, because you need to find both protein and nutrients to have an ideal existence. There are two other elements that come into play; nutrient food sources like berries and fruits will give you a quick burst to your Energy stat but will not keep Hunger filled as long. Protein on the other hand will keep your Hunger stat filled longer but it will also consume some energy when eaten.
There are several berry bushes places in the level to help the your survive and to aid in exploration. A large fruit tree can be discovered to help sustain you after the berry bushes run out of berries. There are also several sources to fish from in the environment as fish are possible found in the deeper areas of water. To true to all survival, water can play a critical role in your existence as finding and drinking from a water source is how you maintain your Thirst stat.
The second aspect of the game is to evolve the character with knowledge you gain from exploring and living day to day. For example you can figure out that smashing two rocks together can result in a sharp rock that you can cut with. Applied to a stick or some wood you can sharpen an end to use to spear fish or other animals with. You can also observe another eating certain vegetation allowing you to know it is safe to eat, or crafting an item of useful purpose. Overall there will be a slight feel of trial and error as well.
A good example is the spear; initially the spear is a combo nation of using a sharp stone on a long stick. (Sharp Stone result from stone v stone contact, Long Stick result from sharp stone v tree.) The spear is simple to make but will increase your options of how you can interact with the environment. With the spear you can hunt by throwing the spear or by thrusting the spear; allowing you to gain additional sources of protein. You can continue to refine the spear by combing in a long stick, a short stick, animal hide, and a sharp stone you can create an alternate spear that will give you bonuses when fishing, but breaks easily when thrown. (Short Stick results from using the sharp stone on a long stick, you get three short sticks for every long stick) You can also upgrade the spear if you have a long stick, animal hide, and a piece of sharp shale to a spear worthy of hunting larger animals like dear and mountain lions. (Sharp Shale results in using a stone on a shale vein.)
