A BIG!!!!! Problem☺

I have a monkey head sandwiched between to planes. When I throw the head against the rear plane numerous times in a row, it goes through the rear plane. Is there anyway to fix it, and no neither the rear plane nor the head is a ghost.

P.S. Do you know of any BGE tutorials?

are you using DLoc to move the head?
DLoc ignores physics and moves an object x units. So using DLoc, it is possible to set an objects position through (or half way through) a wall.

if you want to set your object moving at a constant speed (like DLoc) use LinV. It will need a bigger value for the same results because it sets the velocity instead of the distance traveled, but won’t go through walls.

anyway, that is my guess without seeing a .blend.

I’ve found that the LinV makes it immune to gravity, is there a way around this?

use force instead (not a constant speed)
use python and linV to simulate gravity.

python commented for noobs