diff --git a/tetris.py b/tetris.py
index 4fe5789..43fb805 100755
--- a/tetris.py
+++ b/tetris.py
@@ -3,7 +3,52 @@
 import pygame
 
 
+#
+# Tetrad
+#
+
+class Tetrad:
+    block_rotations = 4
+    block_configs = [
+        [[[1, 0], [1, 1], [1, 2], [1, 3]], [[0, 1], [1, 1], [2, 1], [3, 1]], [[1, 0], [1, 1], [1, 2], [1, 3]], [[0, 1], [1, 1], [2, 1], [3, 1]]], # Shape_I
+        [[[0, 1], [1, 1], [2, 1], [1, 2]], [[1, 0], [1, 1], [2, 1], [1, 2]], [[1, 0], [0, 1], [1, 1], [2, 1]], [[1, 0], [0, 1], [1, 1], [1, 2]]], # Shape T
+        [[[0, 0], [0, 1], [1, 0], [1, 1]], [[0, 0], [0, 1], [1, 0], [1, 1]], [[0, 0], [0, 1], [1, 0], [1, 1]], [[0, 0], [0, 1], [1, 0], [1, 1]]], # Shape O
+        [[[1, 0], [1, 1], [1, 2], [2, 2]], [[2, 0], [2, 1], [1, 1], [0, 1]], [[0, 0], [1, 0], [1, 1], [1, 2]], [[0, 1], [1, 1], [2, 1], [0, 2]]], # Shape L
+        [[[1, 0], [1, 1], [1, 2], [0, 2]], [[2, 1], [2, 2], [1, 1], [0, 1]], [[1, 0], [2, 0], [1, 1], [1, 2]], [[0, 0], [1, 1], [2, 1], [0, 1]]], # Shape J
+        [[[1, 1], [2, 1], [0, 2], [1, 2]], [[1, 0], [1, 1], [2, 1], [2, 2]], [[1, 1], [2, 1], [0, 2], [1, 2]], [[1, 0], [1, 1], [2, 1], [2, 2]]], # Shape S
+        [[[0, 1], [1, 1], [1, 2], [2, 2]], [[1, 1], [1, 2], [2, 0], [2, 1]], [[0, 1], [1, 1], [1, 2], [2, 2]], [[1, 1], [1, 2], [2, 0], [2, 1]]]  # Shape Z
+    ]
+
+
+    def __init__(self, config=0, position=(0, 0), rotation=0):
+        self.config = config
+        self.position = position
+        self.rotation = rotation
+
+    
+    def layout(self):
+        return self.block_configs[self.config][self.rotations]
+
+
+
+#
+# Board
+#
+
 class Board:
+    grid_color = pygame.Color(0xff, 0xff, 0xff, 0xff)
+    block_colors = [
+        pygame.Color(0xff, 0xff, 0xff, 0xff), # White
+        pygame.Color(0x00, 0xff, 0xff, 0xff), # Cyan
+        pygame.Color(0x00, 0x00, 0xff, 0xff), # Blue
+        pygame.Color(0xff, 0x80, 0x00, 0xff), # Orange
+        pygame.Color(0xff, 0xff, 0x00, 0xff), # Yellow
+        pygame.Color(0x00, 0xff, 0x00, 0xff), # Green
+        pygame.Color(0x80, 0x00, 0x80, 0xff), # Purple
+        pygame.Color(0xff, 0x00, 0x00, 0xff)  # Red
+    ]
+
+
     def __init__(self, grid_position, grid_dims, grid_border_width, block_dims):
         self.grid_dims = grid_dims
         self.grid_border_width = grid_border_width
@@ -11,20 +56,10 @@ class Board:
 
         grid_screen_dims = grid_dims[0]*block_dims[0], grid_dims[1]*block_dims[1]
         self.grid_rect = pygame.Rect(grid_position, grid_screen_dims)
-        self.grid_color = pygame.Color(0xff, 0xff, 0xff, 0xff)
-        self.block_colors = [
-            pygame.Color(0xff, 0xff, 0xff, 0xff), # None
-            pygame.Color(0x00, 0xff, 0xff, 0xff), # Cyan
-            pygame.Color(0x00, 0x00, 0xff, 0xff), # Blue
-            pygame.Color(0xff, 0x80, 0x00, 0xff), # Orange
-            pygame.Color(0xff, 0xff, 0x00, 0xff), # Yellow
-            pygame.Color(0x00, 0xff, 0x00, 0xff), # Green
-            pygame.Color(0x80, 0x00, 0x80, 0xff), # Purple
-            pygame.Color(0xff, 0x00, 0x00, 0xff)  # Red
-        ]
 
         self.blocks = [[0]*grid_dims[1] for i in range(grid_dims[0])]
 
+
     def render(self, surface):
         self.render_frame(surface)
         self.render_blocks(surface)
@@ -45,19 +80,52 @@ class Board:
         pygame.draw.rect(surface, self.grid_color, block_rect, 1 if color == 0 else 0)
 
 
-    def advance(self):
-        pass
-    
-
     def block_screen_rect(self, position):
         top_left = self.grid_rect.x+self.block_dims[0]*position[0], self.grid_rect.y+self.block_dims[1]*position[1]
         return pygame.Rect(top_left, self.block_dims)
 
 
-class Engine:
+#
+# Game
+#
+
+class Game:
     def __init__(self):
         self.board = Board((10, 10), (10, 20), 1, (20, 20))
+
+
+    def render(self, surface):
+        self.board.render(surface)
+
+
+    def advance(self):
+        pass
+
+
+    def move_left(self):
+        pass
+
+
+    def move_right(self):
+        pass
+
+
+    def move_down(self):
+        pass
+
+
+    def rotate(self):
+        pass
+
+
+#
+# Engine
+#
+
+class Engine:
+    def __init__(self):
         self.surface = None
+        self.game = Game()
 
 
     def create(self, resolution):
@@ -72,8 +140,8 @@ class Engine:
 
 
     def update(self):
-        self.board.advance()
-        self.board.render(self.surface)
+        self.game.advance()
+        self.game.render(self.surface)
 
         pygame.display.flip()
         pygame.time.delay(1)
@@ -97,23 +165,23 @@ class Engine:
 
         if event.type == pygame.KEYDOWN:
             if event.key == pygame.K_LEFT:
-                self.move_left()
+                self.game.move_left()
             elif event.key == pygame.K_RIGHT:
-                self.move_right()
+                self.game.move_right()
             elif event.key == pygame.K_DOWN:
-                self.move_down()
+                self.game.move_down()
             elif event.key == pygame.K_UP:
-                self.flip()
+                self.game.rotate()
             elif event.key == pygame.K_ESCAPE:
                 return False
 
         elif event.type == pygame.JOYAXISMOTION:
             if event.axis == 0:
-                if event.value > 0: self.move_right()
-                elif event.value < 0: self.move_left()
+                if event.value > 0: self.game.move_right()
+                elif event.value < 0: self.game.move_left()
             elif event.axis == 1:
-                if event.value > 0: self.move_down()
-                elif event.value < 0: self.flip()
+                if event.value > 0: self.game.move_down()
+                elif event.value < 0: self.game.rotate()
 
         return True
 
@@ -130,10 +198,14 @@ class Engine:
         print 'down'
 
 
-    def flip(self):
-        print 'flip'
+    def rotate(self):
+        print 'rotate'
 
 
+#
+# Entry
+#
+
 def main():
     engine = Engine()
     engine.create((800, 600))