Planeswalker by Lynn Abbey is the second book in the Artifacts Cycle, corresponding to the black and white portions of the expansion Urzas Saga. In the aftermath of the Brothers War, Urza has become a planeswalker. Driven mad by his brothers fate and the godlike powers suddenly granted him, he becomes obsessed with finding and destroying those who have corrupted his brother: the Phyrexians. The book is mostly told from the point of view of Xantcha, a defective Phyrexian newt who accompanies Urza on his journey across the planes.
- Aborted Arc: The novel has several subtle hints that Xantcha was created from Mishra's body. First Gix calls Xantcha his "special one" even though there were thousands of newts in her batch. The second is Xantcha mentioning being bad at numbers which is something Mishra also struggled with in the previous novel. Finally, Ratepe comments at one point, "You're more like Mishra than I am, must have been something Gix put in your vat." While this explains her connection to Urza, the story never confirms anything.
- Ascend to a Higher Plane of Existence: Unusually, the novel actually starts off with this event.
- Big Bad: In this book, Phyrexia takes center stage as Urzas archenemy.
- Celestial Paragons and Archangels: A native of Serras Realm at one point explains the angelic hierarchy to Xantcha.
- Dimensional Traveller: The titular Planeswalkers, and by proxy those who travel with them such as Xantcha. The Phyrexians have a technological means of doing this.
- Fluffy Cloud Heaven: Serras Realm has shades of this.
- Foreshadowing: Urzas musings on the possibility of traveling back in time to prevent Phyrexia from coming into existence. Read the next book to see how that turns out.
- Gadgeteer Genius: Urza, once he sets his mind to actually working.
- Heroic Sacrifice: Xantcha and Ratepe save Urza from Gix, ending their own lives and leaving him with only her heartstone to remind him he will never be alone.
- Late-Arrival Spoiler: The Thran have become the Phyrexians.
- Mind Rape: Gix does this to Xantcha.
- No Biological Sex: None of the Newts have a sex, an oversight in their production that nearly screwed Xantcha over when it was eventually realized her intended mission as an infiltrator wouldn't work because of it. She started identifying as female after being mentally influenced by Gix.
- Really 700 Years Old: Urza being a planeswalker, he can look as young or old as he wants to. Xantcha physically resembles a thirteen year old boy, but is actually over three thousand years old.
- Speak of the Devil: The Phyrexians have a strong taboo against speaking the name of their ruler Yawgmoth, referring to him as The Ineffable.