[wise_owl]

Gotta agree with you there unless your game is all about Planet-Destroying conflicts, most of the time if my players asked "How much damage is that weapon doing", my answer would be "Enough....".
A Single weapon capable of destroying a planet in a single shot would be prohbitively expensive, your probably looking at Trillions of Dice of Damage with a significant Armour Piercing ability(I mean what's a planets DR)...