Do overlaid cards lose just base abilities or all abilities from the previous card?
For example: 1.) Sly Deceiver an ability onto a guy. 2.) Overlay the guy via Essence Unbound.
Does the now overlaid guy get to keep the copied ability?
Overlaying vs Permanent Abilities
A topic from AEG's L5R CCG Rules forum, copied for Oracle of the Void from a copy of the forum saved in October 2015, so pages it didn't save are missing. Players' names are left out; the rules officials are named. Rulings are as they stood on these dates; later rulings, the rulebooks and the Rules Archive may differ.
Yes. The copied ability is an ongoing effect that lasts until the end of the game, and the process of overlay keeps the ongoing effects from the overlaid effect. The ongoing effects of Sly Deceiver would linger after being overlaid by Unbound Essence.
Precedent