Radiation Cloud -25% a turn
Nebula Impassable terrain
Black Hole -100% a turn
Gravity Well -75% a turn
Supernova -100% a turn
Blast Zone -75% a turn
Asteroid Field +25% defense

Radiation Cloud Edit

Radiation clouds replace fallout in the Civ4 Beyond the Sword mod Final Frontier. They are very similar, only radiation clouds are green, appear to wave, and don't poison your cities, whereas fallout flashes orange, poisons your cities, and doesn't damage your units. Other than that, they're practically the same. They're both radioactive.