i disagree, it can take out flying units, when upgraded, with one shot so far in my expiriance, and 2 of them on the train level ganging up on one tank unit quikly reduces it to rubbble, if you upgrade the fire rate fully before that level (replay replay replay) then it can save your life, while your marines can deal witht he small fry.
farm at second/third level, up stinger and flamer fire rate to full. on train level, DO NOT GET SNIPERS! i did it with marines and stingers, not oo easy, but its managable without losses.
Hail the chief my advice, cloak instead of heal if possible. try to dodge, but if that is impossible cloak for a second or two while moving to give your self some room.
geos great for up until the train station..then boom no matter whati keep losing people and and even reinforcments arnt helping
snipers die way too easily
my advice. early on, upgrade your life form to et life drain. it SERIOUSLY help when you get surrounded and have no melee form ready. then again thats when you stop using crossbow and starting using rocket launcher.
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