It's...fantastically complex, and a little dry at first.
Once you get the hang of it, it's great fun (for Champions/superhero play, at least, I'll admit that I have yet to use it for anything else, though hopefully I'll have some HERO Fantasy under my belt in the next few weeks). The complexity of the system means you really
can run pretty much anything with it, and it will -- once you and your gaming group know the rules -- run pretty smoothly.
It's an entirely point-buy system, and one that is, in many ways, based around advantages/disadvantages. The GM needs to keep a sharp eye out for abuses of the system, but the book actually helps with this in some instances as certain abilities, and certain dis/advantages, will actually have yield or stop sign icons next to them, as a "heads up" that something is easily abused, or needs to be read over more carefully.
One thing that is both wonderful and terrifying about it, all at once, is that there are many different ways to represent certain abilities. This can be fantastic, but can also be somewhat confusing or overwhelming.
Somewhat rambling (it's 4:00 am) example: I've got a superhero with a shield. I built the shield as what's called a "multipower," which is basically a list of various abilities that I can describe the shield as doing for me, but I can only do one at a time. There's a whole slew of things I can do with the shield -- bash someone with it, throw it all around a room, slash someone with the edge of it, hunker down behind it for an armor bonus, shield someone else with it -- but I can only do one thing a turn with it. This was
my interpretation of what a comic book superhero "shield" should be able to do. My buddy, weeks before that game, had built a guy with a shield, too. His idea of a shield was the "barrier" power (not unlike the Barrier Shadowrun spell) that had advantages built on that let him move it. We could both use our shield defensively -- mine increased my armor rating, his acted as a physical wall in front of him...and the
same GM okayed
both interpretations of a shield. As different as both our "shields" turned out to be, neither one is the same as what a shield does for you in HERO Fantasy, for a classic sword-and-shield type knight.
HERO system is, in other words, almost entirely what you make of it. It's up to you to take the idea you've got for a gadget, and item, a superpower, or whatever...and to figure out YOUR interpretation of it. I could build a poisoned knife that's statted up entirely different than your poison knife. I could even build a
super speedster that uses an entirely different movement power and set of rules than yours...and don't even get started on martial artists.
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That sort of...of...wondrous variety...is often hard to wrap your head around, and can feel very unnecessarily confusing, especially to new players.
Starting cost can also be pretty high, too. The core books -- rules of creating characters, rules for running a game -- will run you $80. World books (for the Champions setting, or Fantasy, or whatever) will generally be $40-$45 apiece. Other books (full of martial arts rules, or the Bestiary, or Champions supervillains, or whatever) are $35-$40.
Depending on how much you
want those secondary and tertiary books -- and someone new to the game probably, and rightfully, wants all the guidance and pre-made stuff they can get -- it can get pretty expensive, pretty quickly. Combined with the complexity of character creation, which makes it a good idea to have multiple core rulebooks (so everyone can read over it and learn the basics, work on their own characters, etc)...it adds up.
As an aside, Hero Designer is their in-house character creation program, and it is
well worth the cost to download. It's also worth pointing out that, in my opinion, their books are very well written, with above-average artwork and -- Champions books in particular -- an amazingly fleshed out, "comic book universe" logical/realistic, world.
Anyways, I'm sorry, I know this is kind of bouncing all over the place...but I've got a lot to say about the system, most of it very, very, good, but at the same time I don't want to lie and tell you it's easy or cheap to get into, or simple to wrap your head around, or whatever. If you've got buddies that already play it, I'd talk to them or see if you can sit in on a game. HERO also has some pretty active forums, and if you're up for it there's Hero Central, a play-by-post sight.
I'm lucky (?) in that I got dragged into the system just a few years ago, as the new guy in a group of folks that've been playing it for years and years. I had lots of help learning the basics, as such, and it really made the transition much easier. If, instead, someone had just thrown the massive, heavy, rulebooks at me and told me to figure it out? I'd likely never have made it through creating my first character.