The most common and most likely answer to this crossword clue is the 12 letter word RESURRECTION
I've seen this crossword clue in Independent
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More clues leading to the result RESURRECTION
Buddy explains!

The straight part
We know that "late riser (i.e. something that makes the late, or dead, arise)" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case late riser (i.e. something that makes the late, or dead, arise) = resurrection.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does RESURRECTION mean?
RESURRECTION noun- The act of arising from the dead and becoming alive again.
- Bodysnatching