This is some stuff I wrote down before. It provides a nice introduction to the game. Its coverage is not balanced or complete, but it is not misleading either. I have put the same content in a blog post:
http://tortoisearts.wordpress.com/2013/03/02/broken-introduction-to-the-design/What is it?An action-adventure-RPG, inside a sandbox MMO.
What are some of its inspirations?Deus Ex, Half-Life 2, Mario, Prince of Persia, Minecraft, Final Fantasy, Smash Bros, Sacrifice, Counter Strike
What are its defining features?Non-linear, rich story, develops in response to player's actions.
Life-like NPCs
Insanely deep, approachable, combat.
Co-op that creates complex relationships between players.
A procedurally generated world that adapts to the player's needs.
In-depth stuffThe main character:So an important quality of this game is that you define your own character, and you don't do it through menus. You do it through play. You make decisions in game, in interesting ways, naturally, and your character evolves to match them. At the beginning of the game you don't even have a character. You are just an ethereal being, with no markings or presence, that watches the world pass on before you. By pressing buttons and moving your mouse/joystick you affect the world and your character develops.
The idea is that there is this world out there, that is my spirit. Everything I like and believe in is there, at least that I am aware of. You can explore it, learn about it, master it. And as you do you make your presence known. You express yourself and you become a part of my world. You create a new place that is a combination of what we both believe. When you are done the campaign your personal setting should reflect the things you felt playing, like a diary, or a second home, a digital one, that gives you back everything you put into it every time you play.
When the campaign is over you are dumped into a free space, and begin to surpass me, creating things more interesting than I did, and learn to express yourself as I have, extending the game, all through it. You join up with other players and do things together, passing on the torch to the next generation. This game is an endless one, in which the players become the creators, and the creators become the players, in a theoretically endless cycle of growth and understanding.
Themes:Space, war, family, society. Picking up girls, or men. Dealing with marriage and children, your parents. Tragedy, fear, oppression, hatred. Meditation, fasting, hunger. Learning to be at peace, to get in the zone, to let your impulses fly out of you.
Karate, kung fu, ninja, battles, medieval war. Samurai, seppuku, honor, sparring, friendship, love. The ancient world. Law, police, gangsters. Solving puzzles, Sherlock Holmes, mysteries, exploration. Working on a team, machines, computers, AIs.
Mechanics:Tactics, action, combat, creation. Platforming, time shifting, parcour. Leveling, monster tracking, capturing, training. Team building.