innerdude
Legend
The answer to the question of "The Most Useful Spell" is now, and always will be, Fireball.
Don't argue with me, just accept it.
"Hey, we need to get through this locked door in the 4th level apartment building--"
"I cast Fireball."
"No wait---!!"
** BOOM **
"Hey, we need to convince that cop that he should just leave us alone."
"I cast Fireball at the cop's police car."
"No wait---!!"
** BOOM **
"Hey, we need to convince the mayor of London that we really can be trusted to work with MI-5 to find the terrorists."
"I drive to the political headquarters of the mayor's closest political rival and cast Fireball into their network data center, making sure that there's no one inside first."
"No wait---!!"
** BOOM **
Don't argue with me, just accept it.

"Hey, we need to get through this locked door in the 4th level apartment building--"
"I cast Fireball."
"No wait---!!"
** BOOM **
"Hey, we need to convince that cop that he should just leave us alone."
"I cast Fireball at the cop's police car."
"No wait---!!"
** BOOM **
"Hey, we need to convince the mayor of London that we really can be trusted to work with MI-5 to find the terrorists."
"I drive to the political headquarters of the mayor's closest political rival and cast Fireball into their network data center, making sure that there's no one inside first."
"No wait---!!"
** BOOM **