The concept behind Complexus is simple. You shuffle all of the pieces together, and draw pieces from a face-up stack (so that you can see the next one on each placement), placing them strategically so that your structure will have as few openings as possible when you run out of pieces.
It contains 3 of each possible configuration of pipes:
- Sharp Turn
- Reverse Y
- Four-way split
- Three-way fork
- Five-way split
It is quick to play, and surprisingly fun. Having 8 openings at the end of the game is a reasonable par.