Post-apocalypse. Survive

The year is 2086. The year the whole world has gone crazy and most countries have declared war on each other.
You're an ordinary survivor amid the ruins of a former, once innovative city. You're alone, and your home is in the new shelter, "Rubezh." It was built by people just like you, from the junk and scraps of military equipment scattered around.
There is currently a conflict between two factions in your city:

1. MechCrips - They use technologically advanced mechs (robots), controlled by both humans and neural networks. Their soldiers are among the most heavily armed armies left on Earth.
2. BioAtlant uses genetic modification to alter the properties of living beings. They transform humans into beasts that reach up to three meters in height and weigh over 350 kg. They are released like dogs, ready to tear apart anything in their path.
   You are not a member of any faction, you are just a spectator who cannot influence the outcome of the war.
   You woke up in your bed to the whistle of ballistic missiles, followed by an explosion. The people in "Rubezh" began to panic and clutch their Berdan rifles, crafted from scraps or taken from other inhabitants of the former world. Unfortunately, your rifle was stolen during your last mission. Looking out the window, you notice MechCrips firing on the inhabitants of your settlement 500 meters away. The soldiers are already heading your way.