I was playing the mission 'The Crucible' and they had a mechanic 'Click to Spawn Locusts'. This reminded me of 'use artifact' from the last mission from Wings of Liberty.
There were achievements associated with the Wings of Liberty mechanic so I tried to hold out as long as possible without using it but had to in the end. Are there any reason why you should not use it? Like a Feat of Strength or something?