Roofing

Cavern terrains have an indestructable border on top, normally making it impossible for anything to go above the ceiling. Super Sheep, Homing Pigeon, Homing Missile, Bazooka and other weapons can go above a cavern ceiling, but Worms are meant to stay below. However, various ways have been discovered whereby a Worm can surreptiously sneak above the ceiling of a cavern map.

Methods of Roofing

1. Tunnel to the left or right top corner with Blowtorch (or clear the terrain with other weapons and make a Girder platform), then Backflip backwards and Parachute to the top. Requires wind not to be more than weakly opposing.
2. Make a ladder of Worms, piled so that each one is standing on the edge of the one below it. With the right positioning, this can be done with as few as just two Worms, and the one on top can simply Backflip up onto the roof.
3. Move a Worm to the edge of the map, with empty terrain above (clear if necessary using weapons; make a platform if necessary, using Girder). Stand on the edge of this worm with another Worm. Use Jet Pack to go straight up and over the ceiling.
4. Attach the Ninja Rope to the the edge of the map, with empty terrain above; inch the rope into a perfectly vertical state; then inch it slightly beyond vertical, and go around the top of the ceiling. This is can be quite difficult to do without practice.
5. Stand almost at the edge of the map, very close to the roof; lay a Mine at the very edge, then walk onto the mine and use it as a platform to Backflip up and onto the roof (before the Mine explodes).
6. Stand at the edge of a girder (or other vertical surface) on the very edge of the map, just below the roof. Do a bump-Backflip and quickly fire and explode a Sheep to blow you up and over the roof.
7. In W:A v3.0, use Silkworm to inject messages into the message stream telling a Worm to point its Teleport cursor above the roof