Help with custom trigger

[daring smelt]

Hey, i have the WA that contains 3 triggers:
• T1 (aura)
• T2 (aura)
• T3(Talent Known)
I need the aura to be showed when one of the conditions is met:

• T1 (aura find)
• T3 (true) and T2 (aura find)
• T3(false) and T2(aura find and remaining time < 8)
  Is it possible to do this with a custom trigger?

[foggy roost]

you can do this
function(trigger)
return trigger[1] or (trigger[3] and trigger[2]) or (not trigger[3] and trigger[4]);
end

where trigger 4 is trigger 2 but with this