Since Nathan first covered it, Rain World has comfortably met its Kickstarter target and been accepted through Steam Greenlight. To celebrate, its small team released new details about the manner in which its slugcat protagonist and world of bat-things and lizard-meanies operate, along with a new trailer.
That ending :'(
From the Kickstarter post:
Further, each predator has its own distinct hunting behavior and specialized senses it uses to perceive you. You won't be able to just out-run them every time, so the only way to survive in Rain World is by learning to understand the capabilities of each creature; their methods and personalities. Can you tell what the Teal lizard is thinking? Notice how he anticipates your movements when coming in for the attack. But also note that despite all its intelligence and aggressive behavior, the patient green lizard is the one that gets me in the end!
I've played early alpha builds of Rain World, and its AI and animation really does make it fascinating just to watch. The lizards hunt you, with different behaviour depending on their head colour, while you hunt the bats and the bats hunt the lizards. There's a bunch of interesting behaviour, like how bats will flap and hide in nests to avoid you, or connect with one another to dangle in long chains from the ceiling.
In the build I played, the physicsy animation was both a blessing and a curse. It brought character to every action in the game, but I sometimes found simple actions like steering down small tunnels harder and more frustrating than it ought to have been. That was six months ago however, a lifetime in game development.
Even if you don't back it, go and follow Rain World's development. They're making something beautiful.