Midnight Massacre

Very basic, and yet very unstable game made in Unity.
It was one of my first games, so dont judge me too hard.
There are 12 types of guns including flamethrower, bazooka, laser gun etc.
4 game modes, story, silent night, arcade and zombie.
Around 13 well designed maps, and 7 enemies.
As I said its pretty unstable, any advices are welcomed.
Thanks for testing my game, cheers, Teraxv.