This crossword No. 9510 clues and answers were published on Tue 24 Oct 2000 and the puzzle can be visited by following The Guardian Quick Crossword No. 9510 link.
All Across Clues and Answers:
1-across – Injure in a treacherous manner : STABINTHEBACK
8-across – Chief : MAIN
9-across – Severely : STRICTLY
10-across – Short prayer service : DEVOTIONAL
12-across – Difficult – adhesive : STICKY
14-across – Proper : DECENT
15-across – Strengthened : REINFORCED
19-across – Killer of famous person : ASSASSIN
20-across – Intravenous administration of solution : DRIP
21-across – Annual steeplechase at Aintree : GRANDNATIONAL
All Down Clues and Answers:
2-down – Farcical imitation : TRAVESTY
3-down – Game of chance : BINGO
4-down – Unpleasantly : NASTILY
5-down – Long-legged wading bird : HERON
6-down – Rustic : BUCOLIC
7-down – Shout – name : CALL
11-down – Candied plant stalks : ANGELICA
13-down – Some – sure : CERTAIN
14-down – Obsolete : DEFUNCT
16-down – Norwegian dramatist, Henrik : IBSEN
17-down – Round-up : RODEO
18-down – Employer : USER
This crossword has in total 22 where 10 are across and 12 are down.