Help! need help with gate trigger

[Reedoxx]

Hi, before i start i want to say im not sure where to post this, but it's a request, so why not here =)

Anyways, i'm doing a map, that have gates in it, but i got a problem to destroy the gates you need to kill the boss, but i don't have the trigger to make it open auto when the boss is dead, instead you can just run straight to the gate and destroy it, which is sad, so would love see somebody show me how to make a trigger to open a gate when a specific unit is dead


The point: help me making a trigger, so the gate open auto' when a specific unit is dead, Thanks !