aok nm its not ven in a loop ur just decreasing the value of the variable on a set trigger ..... ok so then try something like this
Code:
  on 4:text:!skill doom *:#: {
     dec -z %cur [ $+ [ $3 ] ] 
     if %cur [ $+ [ $3 ] ] != 0 { msg $chan $3 has been inflicted with DOOM! }
     if %cur [ $+ [ $3 ] ] == 0 { msg #chan $3 $+ ' s HP is now at 0!!! }
}

hopefully that will show ya what u might need to do to get it working the way u want

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