defence is added up for the entire fleet
if u have 10 ships in 1 fleet with 500 def each, and a fleet attacking that with 4999 attack (after accuracy), then u wont lose any of those 10 ships. another great thing about def is that it renews after ever fleet engages.
if that 1 fleet goes up against 10 fleets each with 4999 attack, u still wont lose a single ship.
dont forget to use absorb
![19](http://spaceoforum.etvirtualworlds.com/Smileys/new2/19.gif)
you probably already knew all of this, but heres the better part.
before the defence is hit by the attacking fleet, the absorb factors in. if u have 80% absorb on ur fleet, than it effectively has 25X the shown defence. 5 times for the absorb, 5 times for the last update, and if u have a swarm bonus, u get between 2-6X more defence actually shown.
depending on the situation, defence can actually be very effective.