Looks like flat head pins. I find those particularly troublesome. Basically the only thing you can do is pry the leg up until enough of the pin is exposed to grab onto with pliers. Heating up the pin will help. You can use a soldering iron but I recommend making it a low temp soldering iron and you'll want to be very careful to not heat it too much. Like press the iron to it for five seconds, then try to move the pin. Rinse repeat until it comes loose. Also make sure the iron doesn't touch the plastic - it'll melt instantly making for a very unsightly blemish. Probably goes without saying but do all of this at your own risk. If you have a junk toy you can practice on, that would certainly not be a bad idea.
