You must enter the Destroyer immediately and cannot leave thereafter.
You may build bridges off the side of the ship to reach things, but those bridges must support themselves and cannot touch the ground.
You may not mine or dig under the ship.
All default game settings, unless you want to turn up the size of the hordes
If you die, the game is over.
You must survive until you are able to build a UH-60 and fly off the helo-deck.