1. Nano Breaker - Konami, 2005 - PS2
It's no mistake that the main weapon in Nano Breaker is called the Plasma Blade. Armed with this sci-fi piece of cutlery, you slash through nanomachine-infected humans who have been unwittingly enslaved and turned into literal killing machines. Slice through them and they spew huge gouts of... "liquid". And it's this fuzzy line between man and machine that makes Nano Breaker unique. Is it blood? Well of course it is. Konami made sure to call it liquid instead, but it looks like blood to us.
At least, it does when it's red. Go to the Options menu and you'll find you can select "Liquid Color." Blue, purple, safety orange - it's up to you, but whatever shade you choose, expect literally gallons of it splattering the walls and floors. Our favorite setting was the multicolor liquid - the resulting carnage makes every stage look like a clown slaughterhouse, or an explosion in a Skittles factory. Taste the rainbow, indeed.