What are proximity mines like? I never got to use one during my playthrough.
Acid debuff? How did you get that?
Proximity mines do about 5-9 damage, as opposed to 3-7 from Grenade Launcher, and this goes up even further with bonuses from certain perks. The only real time I've used them was to foil the path of a Sectopod as it moved into range, thus taking out some of its health and some adjacent seekers that happened to be nearby.
Acid debuffs come from the
Acid Grenade. You get this by researching
Thin Man Autopsy + New Combat Systems (Foundry project), and then building them individually in Engineering. Acid grenades pop clouds wherever you throw them, and DAMN are they useful! They nullify up to 3 points of enemy DR (damage reduction) in addition to the damage-on-action effect and aim/AoE range penalties, making them indispensable when dealing with Mechtoids, Sectopods, and virtually anything that can otherwise tank shotgun rounds with its face. You can even use them to assist in captures! If I throw it on an organic enemy with only 1 health left, then any hostile action or movement he takes after that is going to kill him -- thus, it counts as a suicidal action, which is treated similarly by the AI as moving into an exposed cover position. So they simply won't do anything, letting you Arc Thrower them at your leisure. And even if they do try to shoot, they die quicker than a Sectoid on half health triggering an Infantry with Opportunist + Covering Fire on Overwatch.