A lich could rob someone else of their body. All they needed to do was drive away the original soul, or tear it apart.
However, the bodies possessed by a lich would usually die in two years.
After all, dark magic power was lethal for regular creatures.
A lich could also exist as a soul, but they were very vulnerable in the soul state. Without the protection of a shell, the damage from mental spells would increase significantly.
Therefore, most liches would change their shells frequently.
The shells were expendable for them, but there were exceptions. If they ran into excellent shells that were vigorous and talented, they would try to seize the shells and maintain them well, so that the shells could be used longer.
Roland's body was very vigorous, and he was also a Mage.
