10 Small Details You Missed In Dune

While doing combat training with Paul, Josh Brolin's character, Gurney Halleck explains "the slow blade penetrates the shield." This isn't just a metaphor - this is because in Dune, all soldiers are equipped with personal energy shields that block anything fast-moving from touching them. Unfortunately, they still need to breathe, so anything moving slowly (oxygen, for example) would have to be permitted (unless the soldiers all had oxygen tanks, which is far more costly).

The invention of shields made all fast-moving projectile weapons useless which is why in Dune we see the return to traditional melee combat, with some slight changes. Soldiers must now get in close to their opponent and try to elegantly and slowly penetrate their shield before they can do any damage, all while trying to keep their opponent from penetrating their shield.

With these new conditions, combat had turned much more fast-paced with soldiers trying to stay moving as much as possible to avoid the slow blade penetrating the shield. the movie does an excellent job of showing this new style of combat. They effect of blue to show a block and red to show something penetrating the shield was a nice touch.