Runebound: Artifacts and Allies is, as the publisher's blurb states, and add-on pack to your standard Runebound 2.0 game. It contains a number of new allies, items, and a new type of card, the familiar, that you can simply add to your existing market deck. In terms of ease of incorporation into play, it doesn't get much easier than that.
Each add-on deck is supposed to have a theme, either a literal theme (such as the add-on adventure packs, centered around a location theme), or a game theme, in this case a couple of different game aspects.
First are the new familiars. There are cards similar to allies, although they don't count against your normal limit of 2 allies. And if you plan to use them as allies, don't expect them to stick around long. Most aren't suited for direct combat. However, while you have them, they will boost your abilities in some way, although not always without a price. And most will impose some cost to your hero should they ever perish.
The new items and allies include a smattering of what I'll call "normal" items. Things that don't really change the game any, or stress any new game aspect. There's a set of armor/combat modifiers that allow you to prevent a wound in combat, but also boost your combat abilities some. They're more expensive than just a single weapon or shield/armor would be, as expected, but not so pricey that they aren't useful.
Then there's the batch of cards that I'll call PvP/Interaction cards. These items and allies attempt to force/create more player interaction, either cooperative/negotiation, or direct PvP combat. The most subtle of these involves taking or putting event and encounter cards from or to another hero. Others allow you to negotiate a lender fee for a heroe's allies (with a guarantee they'll get said ally back, even should they die while serving you). And there are allies that will grow stronger if you use them to defeat another hero in PvP.
Overall, I like the familiars, although in at least a few cases (the Demon Cat, for example) the negative aspects make it very unlikely that many people will use them. And the combo armor/weapon cards are highly useful. But the cards that attempt to bring more player interaction do seem forced a little. PvP in Runebound has always been more of an afterthought. It's designed as a multi-player quest/race game. These extra items seem to be an attempt to address the concerns that some have regarding downtime when it's not your turn. However, it seems like an artificial addition.
If you're looking to add some Player interaction devices to your Runebound games, you'll probably like this set. If PvP is something you don't care for, then there's a number of cards that you won't much care for, and will probably simply remove from the market deck. But overall, I think it shows the promise behind Runebound's expandability. With the addition of just a few new cards, some very basic changes were made that created a slightly different flavor to the game.