This page lists every known solution for the clue “A Billion Years” in Crossword Challenge. Because this clue can appear in different puzzles (levels) with different required answers, we first list all the answers, then show which one appears in each puzzle below.
A Billion Years Crossword Challenge Answers (All Variants)
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If more than one answer is listed, open your puzzle page below to confirm the one used there.
All Known Answers for A Billion Years Clue
Where This Clue Appears
Last Checked: November 28, 2025