A deathclaw

After a series of loud thumps it finally comes. Erupting from the ground right on top of the group of raiders is some giant reptile with two demon-like horns and spikes all down its back. Within seconds it sets upon the raiders, using its massive claws to slash and stab at any poor soul who was unfortunate enough to be standing near where it came out of the ground.

Without really thinking you point the minigun at the creature and start spraying bullets at it. With its thick skin the damage you manage to inflict is minimal, but what you do manage to do is piss it off. It averts its attention from the raiders and instead starts bounding at you.

You turn in fear and start running as fast as you can but you're no match for the creature's speed. Within seconds its upon you and with one fell swoop of its powerful arm it sends you flying into the shopfront of one of the stores on the street. You go straight through the window and crash into some shelves, landing flat on your ass. Unable to move after this harsh blow, all you can do is lie there as the creature walks up to you, coming in for the kill.

Once it approaches you it pulls its arms back and retracts its claws, getting ready to stab straight through your power armour and deal the finishing blow. Just as the creature is about to plunge its claws straight into you, you hear a series of gunshots coming from just behind it. You can't quite see who they're from but there are a lot of shots. After the creature lets out a vicious roar the bullets are simply too much for it and it collapses on its side, dead.

With the creature no longer blocking your view you can now see your saviours.