Finally, we get to Radiant. As I'd guessed, this game is definitely inspired by Apocalypse World - the rules summary, which is nice and short, has a series of headings that basically go "To do X, roll Y, then spend your successes on Table Z." AW has a bunch of these, called maneuvers, and so does Storming the Wizard's Tower.
It's hard to guess why people compare it to AW more readily, given that a) Radiant doesn't divide any of its maneuvers by character class and b) Storming pretty much has the same thing going on - though stuff like "to read a situation" or "to show someone up" are more in AW's format, whereas Storming divides these things into broader classes like "Controlling Others" and "Charged Conversations". Fundamentally, the mechanics do not differ very much, although Radiant has you rolling great handfuls of dice instead of a simple 2d6, AW-style.
Anyway - - this game is, to put it one way, an attempt to play Exalted with rules that are actually good. The basic Exalted book is required as a reference for play, as it contains all the setting information and the list of Charms (magic powers, akin to spells) that PCs get. The skill system is interesting in that a regular-use word like Lore refers to solving problems by knowing more than someone else does.
The GM had prepared some pre-made characters for us, along with the scenario he was going to run, which made things a little easier to get started - - digging through our sole copy of the Exalted core book to pick Charms would have been kind of a pain. That's the only detail of character creation that's very time-consuming, though - like in Storming, you establish things like A Friend and An Ancestor, as well as original categories like I Love, I Regret, and I Fear I Will. These things help to color play, and maybe introduce NPCs, but they're mainly a characterization tool rather than a mechanical implement.
I'm still wrapping my head around the conflict system, but essentially you look up a relevant maneuver, roll, and spend your successes on the chart. If it's a competitive action, especially combat or some such, things are a little different - combat tends to involve spending successes to knock points off your opponent's skills, like in Donjon. Reduce someone's relevant skill to zero, and they start losing Essence points instead. Your Essence drops to zero and you, officially "enter a coma", but we took that to mean, generally, that you'd be totally useless and incapacitated for the purpose of the conflict rather than comatose per se.
We never actually engaged the Health Points system, which sounds like a much tougher route anyway - you get to add your Essence score to your pool when you roll to defend yourself from attack, so your opponent has to be substantially more powerful than you (Solars get three Essence, compared to everyone else's two) in order to actually wound you. Given that skill damage is more immediately useful, I can only guess that you go after someone's Health Points when you really, really have to make sure they die.
Another neat, funky thing you can do, either offensively or defensively, is shift the conflict. You can roll the skill+attribute you want to force someone to confront you in a particular way. There's an element called Mobility that I'm not quite clear on yet, but it seemed to play out like this: you have to roll skill+attribute to begin a conflict with someone, and if you succeed you get both the terms of the conflict as you like them (Martial arts! Arguing! Archery! Or whatever!) and you start the process of wearing down their relevant skill points.
If you fail this initial roll, I think they can break off from the conflict and keep their distance from you, keeping their lovely skill points intact. I'm having no luck locating a .pdf of the game, but a story-games.com search will probably produce results when I can get around to it.
Overall, it was a surprisingly flowy, abstract take on a very flexible, action-packed game. The conflict system is fueled powerfully by four factors: creative description, teamwork, and birthrights and charms (cool items and cool powers, respectively). There's a table of bonuses awarded on the character sheet - those factors are the Y-axis and standard/environmental/impressive make up the X-axis.
A good description gives you one extra die to roll; if you work a pre-determined element of your surroundings into your description usefully, that's worth a total of two extra dice. If your description, more or less, impresses everyone at the table, you get three extra dice AND a point of willpower, which can be spent to a) give you one more success or b) if you're defending, knock out all your opponent's successes. Yes, several willpower-bidding wars happened during play; it was great! Given that willpower is required to power Sorcery (very powerful Charm-like stuff, basically), our sole sorcerer in the party had to be very cautious with her willpower, and worked hard to earn it.
If you throw yourself into making really awesome descriptions, you'll have a powerful defensive/middling offensive resource to wield. You can gain willpower from combining Teamwork with Environmental, though, which is nice.
Charms give an absurd amount of extra dice - four for a decent Description, then 8 for Environmental and 12(!) for Impressive. However, Solars have to worry about their auras revealing their nature, the more Charms and Sorcery they use, so lots of sneakiness was called for. Still, we were able to do lots of cool stuff both with and without Charms, so we didn't feel stuck.
I really don't have any complaints at all about this game, aside from the somewhat tricky nature of Shifts in Conflict. That, and a bit of unclarity around how Willpower may be used. Aside from that, it's a solid challenge game with an enormous amount of color and spunk just flowing off of it - good times! It really redeems the Exalted setting and puts it toward some good use.