In the Cybran campaign of Supreme Commander 2, there's a mission with hostile engineers. (I don't think it's a spoiler, since it's obvious up-front what's going to happen, but to be on the safe side I won't say which mission.) I've noticed that the unit AI makes it hard to deal with them: the engis' capture beam outranges the tanks even with the range upgrade, and the tanks won't close to retaliate. Missile tanks and arty are pretty useless until the engis are stationary. Aircraft would be useful, but there are too many AA towers to consider using them at the start. Your own engis won't try to capture or reclaim the enemy ones without specific orders.
It deeply irritates me that this situation is only hard to deal with because of shortcomings in the unit AI. Is there a better way to start the mission than pretending you're playing StarCraft and ordering your tanks to attack each engi as it arrives?