Does a buffed unit lose its buff when it is recalled from the battlefield to base by Zhonyas?

Ruling: No, the unit retains its buff. Units only lose temporary characteristics like buff counters when they change zones, not when they change locations.

Nuances:

• Changing locations (battlefield to base via recall) does not reset buffs
• Changing zones (going to trash or back to hand) would reset buffs
• A unit that is recalled never died, so it never changed zones