Combat uses your Attack rating vs your opponent's Defense rating:
Alice has Agility 12 plus hunting knife skill of 14 for Attack of 26.
Charlie has Agility 13 and staff skill 11 for Attack = 24.
Bob has Agility 8 and hunting knife skill 8 for an Attack is 16. (Obviously, Bob's attack is quite a bit lower than the other characters'. That's because during character creation, Bob's “player” decided to optimize him for Magery, by sacrificing a few points from Agility. Once Bob learns a few spells he should be able to do some cool attack spells instead of using the typical combat attacks.)
The group happen upon a random monster with agility 7 & a small wooden shield (3) for a total defense of 10. The monster has 7 HP.
I should state here that monster stats (and therefore success target numbers) are generally not known to players but are kept secret by the GM. This is not strictly necessary, but it is entirely at the discretion of the GM how much she chooses to reveal. In this example, we show you everything, but don't get too used to it.
So, on our handy-dandy lookup chart, we find the monster's defense of 10 at the top, and follow it down as the black line shown. The pink line is Alice's attack of 26. The green line is Bob's attack of 16, and the purple line is Charlie's attack of 24.
Where the lines cross shows the number to beat when rolling. Alice needs to roll a 4 or higher to hit the monster. Charlie needs to roll 5 or higher to hit the monster. Bob needs to roll 7 or higher to hit the monster. Since all the numbers are lower than 10, it should be relatively good odds to hit so it shouldn't be too hard of a fight.
Our little and of adventurers are in a plucky mood and thy happened to see the monster before he saw them, so they attack first.
We determine turn order by going clockwise around the table starting at the GM's left. Alice is sitting to the left of the GM, so she attacks first.
Now it is the monster's turn. Ooh right, I almost forgot to mention, the monster has Strength of 15 and is carrying a Great Club, for which his skill is 13. So his Attack is (Agil + WeapSkill) = 7 + 13 = 20 and the club does d8 damage.
Now if the monster knew what we know (the defense stats of each of the characters) he may decide to attack the weakest character first. But he doesn't know, so he chooses to attack the first character that attacked him - Alice.
Alice's Defense is 18 (Agil + Armor + Helm + Shield = 12 + 3 + 0 + 3 = 18)
So the GM looks up the monster's attack 20 vs Alice's defense 18, and finds that the monster needs to roll an 8 in order to hit Alice.
Oh dear, Monster rolls a 15 so he hits Alice alright. Then he rolls d8 (great club) and gets a 6. Ouch, poor Alice takes 6 points damage, and is now at 14 HP. But that's OK, cuz it's her turn again, and she intends to finish old Monster off.
Alice rolls a 20! That's a critical hit! That means she gets to choose one of the following bonuses:
Alice chooses double damage, so she rolls d4. Unfortunately she only rolls a 1, which doubled means 2 damage. The good news is that it's good enough to kill this monster, since he only had 1 HP left.
The monster is now dead.
The characters can now search the body for coins or whatever. Alice decides to take the club, even though it is too heavy for her to wield. She can try to sell it back in town.
They also find 10 Gold Pieces which they have to figure out how to divide up between the three of them, and a ring of extra stealth
Alice will probably want to get some healing