damage question!!!!!

Question

when you attack an exact same pokemon with same nature, IV, EV,
why does it do different damage?
For example, when I was playing visualboy on PC, and I saved the game
in middle of the battle(shift+F number), then I attcked
and did almost half of damage to the hp
then I loaded and attacked again, but this time, it damaged bit more than half of hp!
it wasn't critical hit, they were both normal hits.
Why does this happen?

Comments

Wich move did you use?

Answer 1

Damage is a slightly random calculation, while it depends on the offensive stats of the attacker and the defensive stats of the defender it can do slightly different damage. Example:

lvl 100 vs. lvl 100

Suppose Victini has 260 S.Attack and Serperior 260 S.Defense and Victini used Searing shot. The damage would do a minimum of 219 and a maximum of 258 damage, the actual damage is random but will be between those two.

Damage calculation provided by: http://pokemon.marriland.com/damage.php