As I just wrote the V0.7 Walkthrough Update here is a section that might help:
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How to Survive in Combat - Quick Guide
++ You have unlimited moves, but every attack costs Action Points (AP). When your AP are 0, you are immobile until all enemies have taken turns attacking, so plan well. Depending on Engine configuration you have 3-6AP.
++ Level 1 or Level 2 Mobs: Fire until you have only 1 Action Point (AP) left. Then hide behind a rock out of LOS and end Turn(T). Rinse and repeat
++ Level 3 Mobs with Seekers: Do not chase those mobs around the map, they will swarm you with seekers and you’ll die. Nuke all but one in the first round with high end torpedoes. The last one can be defeated with conventional tactics.
++ Swarms (Level 2) open space encounter: Little to no cover. Nuke as many as you can in first round (have them bunch up, AOE is your friend) with torpedos and then slug it out.
++ Match your gear to the level of your mission or you will most likely die Level 1: Standard Photon Gear/Shield/Torpedo ok Level 2: Neutronic Gear recommended Level 3: Quantum Gear recommended
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