Stencyl is one of the more powerful and easier to use 2D game creation tools. It also happens to be a tool that has already been used to craft a huge variety of both commercial and freeware indie games that can be enjoyed either online or on iOS devices.
Then again, merely calling the thing a tool isn’t particularly fair. Stencyl is a fully integrated toolset that comes with all sorts of editors, bells, whistles, and a built-in community that lets creators share games, bits of code, artwork and pretty much everything else without exiting its admittedly beautiful interface.
Now, I’m aware of the fact that that “bits of code” reference might have scared quite a few aspiring game developers off, so let me clarify that you can actually create games with minimal scripting or by simply borrowing scripts from other designers. But, even if you decide to go on and program, Stencyl provides you with powerful tools, an excellent debugger, an almost intuitive and easy to learn drag-and-drop programming language and a friendly and very helpful community. Oh, and its creator has been known to personally help out with particularly tricky problems.
Though Stencyl seems to have so far mainly spawned shmups, platformers and arcade games, trust me when I say you can do almost everything with it: puzzles, sims, RTSs, RPGs and even adventures. And, should you bring some coding and artistic skills to it, you can indeed create something truly impressive, just like Traitor.
Having already finished two prototypes with the help of Stencyl (one of which might just evolve into a proper, commercial game), I frankly can’t recommend it enough. It’s powerful, flexible, sports an excellent level editor and, importantly, offers a fully featured free version that will allow you to create and publish flash games, but also code and test iOS apps.
Should you choose to upgrade to the sensibly priced Pro version, you’ll also be able to properly publish on Apple’s App Store. Oh, and an Android and HTML 5 version is just around the corner, as is version 2.0.