The all pod list with vulkan is a common foe for me though I have yet to face it in 6th.
Once it's down, the units are slow and easy to out maneuver. Here in lies the trick... You need to clump the objectives into 2 very separate spots, ideally out of cover. Then, on the first turn (you will go first if the marine player has a choice) you move your entire army to one set of objectives, ideally the set worth less.
When he drops, it causes several things
If he goes for the bait he drops close to you at which point you redeploy with speed to the other objectives and simply out shoot him. If he drops on the other objectives he looses the benefits of vulkan for the most part. If he splits the drop he looses alpha strike potential and let's you deal with them peicemeal.
So long as your fast and shooty, you should be fine
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