Bastion + Portal - The Gel Cannister

A viscous substance of unknown origin, contained in a scientific apparatus. It's probably not a problem, probably. Might as well smash it open and see what happens.

The most fun I've had with an Easter egg in a while. Not a bad skill either, at least with idols turned off.

As for how to get this, it was in the Arsenal, under the skills menu when I started my New Game+. I assume all you have to do is start a New Game+. I do own Portal and Portal 2, although I doubt they would make this exclusive to owners of those games. It is, however, exclusive to the Steam version of Bastion. I know it looks like I'm on the Xbox if you look at the HUD, but I'm just using an Xbox controller to play.