http://www.youtube.com/watch?v=4Nb5Ohbt1Sg
Imperishable Night. Possibly the most insane shooter I have ever seen. That's an example of the final stage of the game on Insane. I've been playing this for the past couple days - it's a blast, but it's seriously kicking my ass. It's a freeware game, grab it here:
http://indygamer.blogspot.com/2005/0...ble-night.html
This thing has instructions on how to find it in the site - there's a tutorial if you google "Imperishable Night". Not much, but it'll help you out a little.
The download is located under the header:
04/07/07 東方永夜抄 体験版ver0.03 フルパッケージ(19.0MB)
Or, if you want a link to the download directly, http://mirror0.fuzzy2.com/zun/eiya_tr003.lzh