In the fall of 2006 and spring of 2007, I was involved in a class project to create a mod for Unreal Tournament 2004. The mod we worked on was called Viathan. Part of the concept was that, similar to the Metroid games, there would be certain obstacles that could only be bypassed if the player had access to the correct type of weaponry. This pod hung from the ceiling and blocked the hallway, but if the player shot if with lightning it would deflate, allowing passage.