Scatter the Jackals
At one point, you can go up a ramp-like rise and look down on a whole bunch of Jackals gathered in a circle. You know what to do next, right? A well placed grenade or two can send them flying in all directions, heh heh. But it's even more fun to walk right up to them and dump a frag grenade right in their midst, taking them all out with near-perfect symmetry. Their collective alarm when they see you is also amusing.