
Paul Dunn's winning solution in a revisit to puzzle 52: Bacteria Energy, which appeared as Puzzle 700 in 2013.
Here are all the revisiting puzzles to date.
Most of the puzzles in the regular series have been revisited six times since their initial run.
The first column, "original puzzle", links to the original puzzle on the Foldit website.
In the second column, "puzzle guide" links to a guide page for each puzzle. The guide pages summarize what's known about each puzzle.
See revisiting puzzle results for the complete history.