From Worms Knowledge Base
|Standard effects:|| 75hp injury from sheep (max.), Large crater|
30hp injury per missile (max.), Small crater
The Mega Sheep acts exactly the same as the Super Sheep, except for the fact that it can drop 3 missiles by pressing the Spacebar (or Enter on the Ninja Rope) while flying. After all 3 missiles are used, pressing the Spacebar will make the sheep drop down and explode on contact, like the Super/Aqua Sheep would.
When the sheep exits its flying mode, hitting the Spacebar (or Enter on the Ninja Rope), will cause the sheep to explode instantly, assuming the sheep didn't make contact with anything at that moment, and was still in midair.