You slip into the crack to the Big One's left as it closes the distance. For several moments, you hold your breath as the soft stamping footfalls get closer and closer.
You can hear it's breathing now. It's different than the hissing of the smaller ones. It sounds more like a bellows that keeps a blacksmith's fire roaring.
The creature appears and you ready your spear, but it spots you immediately as you lunge forward. It rears up and you to miss. You go into a roll and pass under it, trying to get on its blind side. The tunnel is narrow, but the Big One can still back up. It takes several steps back and you stand to face it.
It lunges forward and you parry with the spear, trying to slash at its good eye, blinding it completely. It twists its head so that the spear glances off the thicker skin above its head. Before you can attack again, it swings its cranium around and headbutts you hard. You hear a popping sound as your arm breaks and you're thrown against the wall, howling in pain.
The Big One looks at you, and you get ready for it to finish you off, but you both hear something. The creature looks away from you and moves forward again. You think you hear yelling, but the injury has drained your strength and you pass out.
When you wake up, still alive to your amazement, you find that you've been moved back into the cavern and your arm has been cared for. The translator is there, and he explains that the guards heard the fighting and came to assist you. You stalled it for long enough that they were able to gather enough people to overwhelm it. The Big One is dead, and the lizards have scattered. The war is over. He assures you that the princess will be by soon to congratulate you on your bravery, and for now you'll have to recuperate some before you're able to travel again and make the hike back to the village. Still, in all, you're feeling pretty good.
The End.