While taking some boots off one of my Dragon model soldiers I had to take off the feet but now I cannot put the feet back on. The pegs on the feet are so much wider than the holes on the leg it's almost impossible. I have tried with all my strength but cannot pop them back in. Is it possible hot water can expand the hole or maybe should I try lube? I do not understand why it is so difficult? I do not want to break the figure putting the feet back on please someone help!

Try putting the feet in the freezer for a few hours and soaking the legs in hot water. This way you get the most differential between expansion and contraction. You might also rub graphite powder or bar soap on the pegs. If you don't want them to come apart again, a little epoxy will keep them firmly in place.

well I tried as you suggested but it's just not possible with my lack of strength. Is it possible to set the feet pegs on fire so they go soft then blow them out quickly? I'm willing to try anything at this point lol

What about sanding (or filing) the pegs down to a smaller diameter? You may need to use glue, but at least they'll fit.

Auger out the holes in the legs.

I finally did it. Ended up trying something else. I did a macgyver and pryed open the leg hole with some scissors and then used a toothpick to keep the legs apart just the tiniest bit which made the hole that much bigger and I rammed the feet in only thing is I got some skin pinched on side of my thumb bloody well hurts still nice bruise nearly took off skin lol
thanks again for your help guys