More Planeswalking info

"It won't need an ambulator. It can walk the planes directly. Even you could guide it safely."

"I wouldn't know where to go."

Xantcha had conquered her fears, but no matter how hard she tried, she couldn't orient herself in the betweenworlds emptiness. Worlds-planes-didn't call out to her the way they called out to Urza. If she lost her grip on Urza's hand, she fell like a stone to whatever world would have her. Urza's armor kept her alive through one failure after another, until Urza conceded that she'd never 'walk the planes.

***

Planeswalker, Chapter 10