Unlimited health or ammunition:
Stand, crouch, or lay near any one of the replenishment depots.
Camp there with a sniper rifle and keep firing.
Battle Of Hoth (Galactic Civil War): Destroying AT-Ats:
Another way to defeat the walkers is to take control of the Snowspeeder
as the pilot. When you get near the walkers, switch places so that you
are in control of firing the tow cable. When the cable is attached, the
CPU pilot in the speeder with you will complete the final wrap around.
Killing a Jedi is difficult. Get a vehicle that is able to fly. Go to the
enemy Jedi and wait until he stands still. Then, land on top of him.
He will respawn. Do this as many times as desired.