i ahve a slight problem with the death triggers.

my trigger goes like this
player 1 brings at least 1 terran scv to location 10
player 1 brings at least 1 terran scv to location 11
actions:
display text message:blahblahblah
kill all protoss pylons owned by player 1 at location 12
kill all protoss shield abtteries owned by player 1 at location 12
display text message:blahblahblah
set countdown timer :480 seconds
player 1 set death to 0 samir duran
player 1 add 1 death of samir duran.
player 1 set death to 1 samir duran