I had an idea for the mouse AU and how Cross befriends Horror.
The three little mice have to wait until Horror is sleeping somewhere before they can go out and look for food. They have some dried berries, nuts, and insects stored in Killer’s burrow, but with three mice to feed, it wont be enough. They need to go out and scavenge for anything edible.
One day while they’re out looking for food, Reaper (a raven) finds them. They try to get away by going through a brier patch, but Cross’s hood gets caught in the thorns. Reaper manages to catch up to them. He can’t go into the brier patch, but with him so close, he’ll catch them as soon as they try to leave. Since he can’t get them right away, he starts taunting them, “ah, little morsels gathering together to form a meal for me. How nice of you to save me the trouble of catching you one at a time.”
During the commotion, Horror wakes up from his nap and finds the tracks the little mouse group left and follows them. When he finds the group cornered in a brier patch and a raven waiting to snatch them up, he becomes angry. He’s waited for several days to catch this group, and at this point, he’s too hungry to give them up to some bird. Too hungry and angry to think of the consequences, Horror attacks Reaper. He manages to get a few bites and scratches in, since he attacked him from behind while he was distracted with the mice. While the two predators are fighting, the mice manage to get out of the thorns.
Unfortunately for Horror, Reaper is much stronger and manages to overpower him. He has the rat pinned to the ground, his talons sinking into his flesh, “well now since you’ve made me loose my lunch, you’ll make a fine replacement. A rat the size of 3 mice is a good trade.” Hearing the rat’s pained squeaks, Cross is reluctant to leave. He wants to go back and help, but Dust and Killer hold him back. Luring a badger away is one thing, but Reaper has flight on his side, so he’ll be much harder to get away from if they manage to get him to let the rat go.
Before Cross can do anything rash, a loud bang sounds in the forest – even Reaper startles at the sound. A hunter is near by. While Reaper is distracted, Horror bites his foot, making the bird release him. The rat lets out a growl, showing that he still has some fight left in him, but Reaper isn’t willing to stick around any longer with a hunter in the area. As the raven flies away, he calls to the rodents, “you were lucky this time, but one day that luck will run out. Death calls to everyone eventually.”
With the raven gone, Horror’s adrenaline fades, and he collapses in the snow. Everything is quiet now, so Cross cautiously approaches, much to Dust and Killer’s irritation. Killer hold onto Cross’s tail to prevent him from getting any closer to the rat. Now that he can see the state that Horror is in, bloody and trembling, Cross knows that even if Reaper doesn’t come back to finish him off, he won’t survive the winter with wounds that deep.
Cross gives a pleading look to Dust and Killer, wanting to help the poor rat, but they aren’t going to let the mouse get himself killed. Dust tells him coldly, “just leave him. Even if you did help him, he would just eat us anyway. Besides, it’s better this way. Now we don’t have to worry about him hunting us anymore.” With two against one, Cross has no choice but to leave Horror and follow the others back to the burrow. However, once Dust and Killer are asleep, Cross takes a few nuts and berries back to the rat. He knows the rat might be hostile towards him, so best to bring a peace offering.
Horror is still in the same spot where he left him, luckily Reaper didn’t come back for him. The rat growls when he hears the mouse approaching him, but when he puts a nut in front of his nose, he quickly quiets, snatching it up and eating it vigorously. Seeing this, Cross realizes that the rat hasn’t eaten in days. He wants to bring him back to the burrow where he’ll be safe and warm, but he’s too small to carry him, so Horror will have to move on his own. Using a dried berry, Cross beacons to the rat, asking him to follow and promising that there will be more food and a warm place to sleep as long as he doesn’t hurt him or the others. Horror doesn’t respond, but with the promise of food, he follows.
Once in the burrow, Horror immediately sniffs out their food stores and starts munching away all their food. Cross worries that he will eat it all, but how can he tell him to stop? Would he even listen if he tried? At least with the food distracting the rat, he’s able to get close enough to clean his wounds. Horror is hesitant to trust the mouse, but he gave him food and a safe and warm place to sleep…
“Horror…” Cross’s ears perk up when the rat spoke for the first time. He tilts his head in confusion, so the rat spoke again to clarify, “my name….is Horror.” Deciding that this would be enough to satisfy the mouse for now, Horror curled up in the nest to sleep.
Dust is furious with Cross when he wakes up to find a giant rat in their nest. How will they survive now that the rat has eaten their food and the nest is no longer safe? While Cross and Dust argue, Killer notices that the rat hasn’t woken up despite how noisy the two mice are being. He cautiously boops his nose. When Horror doesn’t even twitch, Killer concludes that he must’ve gone into hibernation. He tells Dust that he won’t be waking up until the snow melts, so the nest will still be safe.
Even if the nest is safe, they still need to worry about food. Killer decides to go into hibernation as well, this way only Dust and Cross will need to eat, so they won’t have to find as much food. Dust still doesn’t like this, he wants to kick the rat out of the nest, but he isn’t strong enough to do it himself, and Cross certainly isn’t going to help him. He has no choice but to accept the rat into their nest.