How about a deployable mine field, deployed by squad leader ( for avoiding issue ) as FOB/Cache defense. As a respect to international treaty i would be mark. We can have a wire at one end, and some white rock pile infront with a red triangle. No it wont be a weapon a massive destruction, its a defense multiplyer. To make it worst, if any one can with the idea of "its a deployable i just have to destroy it" make the mine stay. But now with no mark, except if rebuilded.
Ottawa treaty specify that is entirely legal.
I also tought about APMF but i think it would be "over-killing"Only anti-personnel mines are covered. Mixed mines, anti-tank mines, remote controlled claymore mines, anti-handling devices (booby-traps) and other "static" explosive devices against people are not within the treaty
But alot of faction in PR havent sign the treaty

