Crossword puzzle clue "ones responsible for what's missing from certain puzzle answers"

Ones responsible for what's missing from certain puzzle answers?

Instrument that hints at the missing parts of certain answers in this puzzle

Movie good guys responsible for the circled squares in eight long puzzle answers

Chop-chop (or... the last name responsible for the four one-word songs at the end of this puzzle's longest answers)

Landmark that, in a way, is a border feature of this puzzle and a hint to what's missing from 10 answers

This weekend's fridge contents, probably, and what's missing from five long puzzle answers?

Julian Assange's controversial website, and a hint to what's missing from this puzzle's four longest answers

Psalm 100 excerpt suggested by six puzzle answers and graphically represented by certain black squares in this puzzle