Class 3C is a toroidal spaceship with the top of the 6x6 tile grid wrapping around to the bottom and the left side wrapping around to the right. Since lasers require an empty space in front of them – and engines an empty space behind them – your ship must have holes in it to accomodate those building requirements, and the larger and more numerous the holes, the more you must pay in insurance costs prior to launching your spaceship.
Class 4C has space to build four separate spaceships, but when the sand timer is flipped the first time, someone rolls a die and players can now build in additional areas of the game board in order to connect some of the ships. When the sand timer is flipped a second time, the die is rolled once more, possibly providing additional building sites.
