[Trigger] Gui/Jass help

[Nailgun]

Map system help

I feel very stupid for asking this, seems as if it should be a very simple trigger.
Essentially I want every unit who's custom value is 1 to have steadily lowering health and mana on a time interval.

• Events
  • Time - Every 5.00 seconds of game time
• Conditions
• Actions
  • Unit Group - Pick every unit in (Units in (Playable map area)) and do (Actions)
    • Loop - Actions
      • If (All Conditions are True) then do (Then Actions) else do (Else Actions)
        • If - Conditions
          • (Custom value of (Picked unit)) Equal to 1
        • Then - Actions
          • Unit - Set life of (Picked unit) to ((Percentage life of (Picked unit)) - 2.00)%
          • Unit - Set mana of (Picked unit) to ((Percentage mana of (Picked unit)) - 2.00)%
        • Else - Actions

And every time I try this, five seconds into the game my hero dies. Right now I would just like a solution, so JASS (Not vJASS please) AND Gui are accepted as suggestions. Thanks for your help in advance.

 

[ap0calypse]

Creepy
I've used the exact same trigger, 2 units had custom value 1 (hero and footman, not that it matters), 1 did not and the ones with value = 1 slowly degenned HP the way it's supposed to work.

Can another trigger be the cause of this?