I know that magnets have been suggested dozens of times before and rejected, however I have really thought this through and come up with a new way of looking at it.
This will need a new layer, the Field (B) layer that can be turned on and off like newtonian gravity, and two elements:
NPLE North pole, red in colour. SPLE South pole, white in colour.
HOWEVER
My suggestion differs, because these magnetic fields do not behave like gravitational fields.
Uses:
"Braces for Flames"
Actually, this one sounds a lot more knowledgeable than most of the others. You actually make it sound possible!
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I can see it breaking electronics. Wires conducting electricity generate magnetic fields, which then induce a current in the wire, and so on, essentially turning the wire into a battery with a ridiculously strong magnetic field.
That's why it's an option (like Newtonian Grav) that can be turned off.