I ran across this gem a few months ago while searching for a generic ruleset that isn‘t too crunchy, too squishy, bland or simply not fun. Tried and tested a lot of them and finally found the Adventure System by chance.
The designer states in the preface that he started homegrowing his rules a long time ago in the 1980s and it shows. This is not an armchair designed system but instead gives the feel of being tried and tested for a long time.
There are a few things I like im every system I encounter (mostly the omission of class and levels) and it hits the sweet spot between just enough crunch and handwaving a bit too. Adventure System seems to be heavily influenced by Savage Worlds (or at least bears a very strong similarity to that system). Having played Savage Worlds for a long time and liked it, this is not a bad thing at all.
So, why bother and not just use Savage Worlds? Adventure System IMO does some things better:
First, it does away with modifiers - as in: at all. To quote the designer: „ all conflicts are resolved using dice mechanics without any modifiers. You roll a die and take the result at face value without adding or subtracting any modifiers from that value. Advantage and Disadvantage replace circumstantial modifiers. This simple yet critical concept removes almost all calculations from game play.“
And it does. The system flies. Circumstantial modifiers give you an extra die to roll and you take the highest or lowest result. You just roll the specified dier against a Difficulty Number of 4, 8 or 12, depending on what you try to accomplish.
In the case where the rules specify something like a modifier, the system means a die step. Just increase or decrease the specified die type by the number of steps noted. For example, if the character has d6 Strength and wears a Ring of Mighty Brawn +1, he now has d8 Strength.
What‘s more? There is the so called Compass, an alignment system of sorts, based on Honor, Morality and Sanity. Each starts at 0 and can go from +8 to -8, depending on the actions of the character during a campaign. This has mechanical implications, as - for example - a character’s Morality equals or exceeds +4, they are Trustworthy and gain Advantage on Persuasion checks, whereas if their Sanity equals or drops below -4, they are Disturbed and gain Advantage on Intimidate checks, but must make a Spirit check or gain a disorder.
The rulebook is very complete, it covers templates for the usual EDO suspects, Futuristic Characters, Vehicles and much more. In sharp contrast to Savage Worlds, powers largely come pre-built in the form of - well - powers, several types of magic and elementalism.
All in all, coming from Savage Worlds you will find yourself right at home but notice that some things handle smoother and/or faster and that the rules have an interesting spin of their own. If anything, die rolls in and out of combat are resolved really fast and the system does a wide range of genres well, from Classic Fantasy, to Cyberpunk, to Space Opera, to Weird War II and much more.
Artwork and layout is nice and functional, the sepia-toned background makes it easy to read and it has an index. The only minor quibble is that there isn‘t a character sheet in the rulebook, so don‘t forget to download one as well. Adventure System clocks in at 220 pages and is available as pdf or hardcover. I own both, the hardback is of high quality, but my first one got roughed up in the customs, so DriveThru send me an replacement.