Can I make a trigger activate when a certain number of specific units die?

[laverniusregalis 10]

I'm making an armored mission, and I want to set the mission up to fail if three or more of the player's Marshall APCs are destroyed. Is this possible?

[kylania 567]

Name your Marshalls something like: lilly1, lilly2, lilly3, lilly4.

Then trigger condition of:

{!alive _x} count [lilly1, lilly2, lilly3, lilly4] > 2

[laverniusregalis 10]

Thanks.