6 down
Fossil
fuel
left
dons
suffering
agonies
(8)
Fossil fuel left dons suffering agonies (8)
hints
0
checks
0
hints
The definition is at the beginning of the clue.
How the clue works
The definition is Fossil fuel. "Suffering" is your anagram indicator, and the letters to scramble are agonies plus L (the standard abbreviation for left) — with "dons" being the hint that the L gets put on with the rest.