TRI-HEX

Each player drops a triangle group of 3 pieces (2 of its color) on empty cells. A triangle may also be dropped with pieces overlapping other triangles provided the colors do not change, and at least one previously vacant cell could not be filled by a regular move.

Sample Game:  
    ___xx_______oo__ (was swapped)
1.  f4  ne    l8 n
2.  p6  sw    o9 ne
3.  u7  sw    n4 s
4.  j6  ne    s7*nw  
5.  u5  sw    u11 n
6.  z8  sw    u9 ne  
7.  x6  sw    resign  

Final Position:

             X X X
: abcdefghijklmnopqrstuvwxyzABCDEFGHIJK  
| . . . . . . . . . . . . .             1
|  . . . . . . . . . . . . .            2
|   . . x . . . . . . . . . .  O        3
|    . o x . . x . . . . . . .  O       4
|     . . . x o o . x o . . . .  O      5
|  O   . . o x x o o x X O . . .        6
|   O   . . o o x o x o X . . . .       7
|    O   . . x . o . x o x o . . .      8
|         . . . x o . x o x . . . .     9
|          . . . . . o o . . . . . .   10
|           . . . . . x . . . . . . .  11
|            . . . . . . . . . . . . . 12
|             . . . . . . . . . . . . .  
: abcdefghijklmnopqrstuvwxyzABCDEFGHIJK    
                    X X X