You should be careful with such spells. In Terry Goodkind's The Sword of Truth series a spell was mentioned which erased the memory of a single person from everyone's mind... It had the unpleasant side effect of eventually unravelling all of reality due to mismatches.
Isn't it a 64-fold increase in energy is a doubling of damage at double the distance (if you are talking about the Kiloton spell)? BTW, this spell describes the effects on someone close by - what are the effects on someone who is affected from the inside?
About a planet's hitpoints.
http://en.wikipedia.org/wiki/Orders_of_magnitude_%28energy%29
A person wielding a baseball bat (a couple HP damage), = 80 joules.
Energy released by the 2004 Indian Ocean earthquake (barely felt by Earth's main body), = 1.33 × 1^20 J.
Earth's gravitational...
But will you have the proper coordination and mind for watching and analysing everything, everywhere and everywhen? Strong in the Force, you will be, a Jedi, you will be not.
What about balancing the Overlord's true form in the Gates of Hell?
One user on the Wizards.com board once suggested that every worshipper of a deity should be considered an additional spellcaster for epic spells.
While this certainly is unbalanced, I thought that perhaps a deity should recieve certain bonuses according to the number of worshippers. I composed...