Here are the possible solutions for complete with down clue
Answer
Clue
Relevancy
four
Clue
Number of times this puzzle's theme word appears diagonally in the grid (to complete the puzzle, shade those words plus the Down answers that begin where they meet)
Definition
the cardinal number next above three
nail
Clue
Complete, with "down"
Definition
to fasten with a long slender piece of metal
sam
Clue
Singer Smith who said the likeness between his "Stay With Me" and Tom Petty's "Won't Back Down" was "a complete coincidence"