RuneQuest 6 is a game built on skills. That shouldn't be a surprise to anyone that has heard about RuneQuest, Stormbringer, Call of Cthulhu, Basic RolePlaying, Legend, Elfquest, OpenQuest and I'm sure a slew of games that are a variation of the above. They all have their roots in the first release of RuneQuest.
There are some basic things to note about skill use in RQ, especially for those coming from the D&D side of the table - it's percentile based and you want to roll low.
Going back to D&D and it's many offspring. In D&D, you usually want to roll high, a natural 20 always hits and a natural 1 always misses. That is D&D combat broken down to it's simplest core.
In Runequest (and it's related siblings and offspring) you pretty much want to roll low. A roll of 01-05 is always a success and a roll of 96-00 is always a failure. Equal to, or less than your skill value on your D100 roll means you succeeded and rolling greater than your skill value means you failed. That is RQ skill resolution at it's simplest core.
D&D variations sometimes have criticals and failures. Generally a natural 20 is a crit (sometimes there is a range, say 18-20, but it is always a natural roll that you are looking at, not adjusted by bonuses) and if there are fumbles, they occur on a natural 1.
In RuneQuest 6 criticals happen when the roll is 1/10th the skill value (adjusted after modifiers - this shit I remember from older editions of the rules). This applies both in combat and with non-combat skill use. Fumbles occur on a roll of 99 or 00 (2% chance, compared to D&D's 5% when applicable).
RQ6 includes grades of difficulties from Automatic (no need to roll), Very Easy (double your effective skill value) all the way through Herculean (skill effectively reduced to 1/10 value) and Hopeless (no chance, no tries, no can do). There is also an alternative chart if multiplication slows you down too much.
As you can probably see, RQ6 is much more granular than D&D, which is where I am firmly based. It's funny, but reading through the RQ6 rules makes me want to break out my copy of Basic Roleplaying and whip up some cross-genre game, with fantasy elements taken from RQ6 and stealing ideas from Rifts. I do think BRP or RQ6 could handle such a setting better than Rifts current buggered beyond redemption rules, but I have suddenly veered off on one hell of a tangent!
Where was I? Oh yeah, RQ6 skills. The rest of the chapter describes the skills that you assigned points to in the previous chapter. It includes examples of what may happen on a crit, a success, a failure or a fumble. The examples are pretty much good enough for a GM to extrapolate what he needs for his unique situation.
There is a section on Skill Rules for Different Circumstances and Situations at the end of the chapter. I'm just going to list the different rules, as some are fairly obvious what they deal with based on their title, and in any case, I'm not trying to repeat the book, but show what it has inside.
So, that being said, here we go - Reattempting Skills, Augmenting Skills, Capping Skills, Contested Rolls (always a biggie) and Group Rolls. Some of these are broken down further (Contested and Group Rolls for example) but that should be enough to get an idea.