For me it’s easily refining liquid morkite. It takes forever. I swear half the team is off staring at a wall while you get the pipes built. Lastly, I can’t quite out my finger on it, but the refining portion feels so scripted and boring…Every other mission type is a blast.
Hot take: but the one with the giant drill. It’s really cool the first time but otherwise it’s gets repetitive waiting on top of the drill until you reach the destination. The final fight also usually plays the same.