Tris

Tris is a 2006 game by Daniel Solis.

The game is played on an 8x8 board, initially empty. Each player has enough pieces of one color (probably 40 is more than enough).

Rules:

• On his turn, the player either:
• drops a friendly piece, on an empty square, at the first/last row or vertically connected to another piece (or either color)

 all legal next drops shown

• moves a piece to a horizontally adjacent empty square
• then, the piece 'falls' until meeting another piece (falls in the direction of the edge supporting its column of vertically connected pieces)
• if there were pieces on top of the moving piece, those pieces also 'fall' 

all movements available

• If, after the drop/move, an orthogonal or diagonal 4 in-a-row of pieces of the same color is made, those pieces are removed from the board (cf. next rule for exceptions)
• the remaining pieces fall accordingly, which might produce more 4 in-a-rows, and so on...
• Fixed pieces: the pieces at the first/last row are fixed and cannot be removed
• when a row is full, those pieces also become fixed
• A player wins if either:
• his first four rows are full
• twelve of his pieces are removed
  

Comment from the author: Pretty simple game here, essentially taking elements of Tetris and Connect 4 and laying it flat on a board instead of vertically.