Wellgabber Apothecary

Oracle Text

1W: Prevent all damage that would be dealt to target tapped Merfolk or Kithkin creature this turn.

Card Rulings

10/1/2007 The targeted creature must be tapped when the ability is activated and when it resolves. It doesn’t need to remain tapped in between.
10/1/2007 Once the ability has resolved, all damage that would be dealt to that creature for the rest of the turn will be prevented, regardless of whether it’s tapped or untapped at the time that damage would be dealt.