The following is an example of how combat is conducted.
Tiberius Flagstrom comes across a warped demonic entity known as a Hulking Damned (it's not a troll, honest!) and decides that he wants to kill the creature in order to proceed. To decide who is quickest to react, each rolls 2d6 and adds their Athletics attribute. Tiberius wins easily.
As his move action, Tiberius engages the Hulking damned in melee combat using his Deathlover Sword.
He now uses his attack action. He rolls 2d6 and adds both his Fighting bonus and the bonus he gets from his Deathlover Sword, which is +2 and +1 respectively. His total attack value is 12.
The Hulking Damned now rolls for his defence. It needs more than Tiberius' attack value to successfully defend. It rolls a 5, then adds its defence bonus of +4 and the armour bonus from its Leather armour, which is +1. Its total defence value is 10, which means that Tiberius has struck a blow.
Having hit the Hulking Damned, Tiberius rolls his weapon's damage dice. The Deathlover Sword deals 1d6 + 1 damage. Tiberius rolls a 4 for a total of 5 damage, which is deducted from the Hulking Damned's current HP.
This is a very simple combat example. Advanced rules for combat include two-weapon fighting, total attack, total defence, steady aim and concealment modifiers. There is also the possibility of substituting an action for a Task Check in order to see if the hero can do something cool, like disarm a creature or launch them into a trap.