How to make a potion of mass destruction

Introduction

You take control of a mad chemist who has recently found in human DNA certain types of proteins which, if they are combined with some specific compounds, can really make a poison of mass destruction.

How the game works

First you have to find a victim walking around the city. 

Once you find a person, the process of extracting the proteins will begin. However, the people around you will try to stop you from extracting the proteins, so you'll have to knock them out. 

Finally, when the potion has reached its full capacity, the mad chemist will poison the whole world.