Backpack Cannon: Found in a couple of forms. The primary one for those of us whose body plans resemble the ones we’re used to, which is to say, vertical, involves using a backpack to hold vertically-launching smart missiles and other such guided support weapons that don’t need to be aimed in the direction they’re firing in. (Fortunately, combat armor, powered or otherwise, avoids the problem of setting yourself on fire doing this.)
The other form is regular heavy weapons for those people with horizontal primary body axes, which isn’t every quadruped, hexaped, etc., but is a strong working majority.
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