[There's a little less shooting involved, at least, as far as Irisa's concerned. She prefers her knives over guns.]

Nothing like that. After the Arks fell, and terraspheres on board terraformed the Earth, it changed a lot. Many plants and animals were mutated, becoming a cross between what they once were and what was carried on board the Arks.

The wildlife is dangerous, more likely to eat you than you it.