Monorail
Used as Death Match of Season 3, Round 10 and Season 4, Round 6. (Discussion of S4E6 in particular will come later.)
Rules
The objective is to be the one that completes a train track, or to be the one that declares it’s impossible (correctly).
There are 18 square tiles used in the game. Two of them show straight tracks, the station tiles, which are already placed on the grid; the remaining 16 tiles can be made to show a straight track or a bend track, which are to be placed. Players place tiles so that sides match (a track leading to a non-track side is not permitted; think of tile-based games (such as Dominoes or Carcassonne, where sides of tiles must match). A player may place one to three tiles at once, but all of them must be played in a straight line contiguously (think of Scrabble, where you cannot place your tiles separated, only that it’s even more strict; the tiles must be contiguous, not separated by already existing tiles). However, the track itself doesn’t need to be connected; as long as the tiles placed are connected, it’s fine.
The person who places the last tile, completing the track using all tiles already placed, wins. However, a player can also declare that it’s impossible to complete the track, in which the opponent must either complete it (for a win to the non-challenger) or resign (for a win to the challenger).
Also see this video from the Facebook page, which is unfortunately in Korean, but gives illustrations.
Chaos at the Sky 