When comparing Stencyl vs Blacksmith 2D, the Slant community recommends Stencyl for most people. In the question“What are the best 2D game engines?” Stencyl is ranked 11th while Blacksmith 2D is ranked 48th. The most important reason people chose Stencyl is:
Power users can also write code in Haxe (similar to Actionscript 3) to create their own custom classes and extend the engine.
Specs
Ranked in these QuestionsQuestion Ranking
Pros

Pro Haxe scripting available for advanced users
Power users can also write code in Haxe (similar to Actionscript 3) to create their own custom classes and extend the engine.

Pro No coding required, great drag & drop interface
Visual scripting in Stencyl is based on the MIT Scratch project, which was designed to teach programming. Script elements fit together like puzzle pieces, ensuring that data and function types cannot be mismatched.
Pro Cross-Platform
Publish iOS, Android, Flash, Windows and Mac games without code.
Pro It's a NO-CODE Program, you can add logic without code
Pro The original concept for Ghost Song was created using Stencyl
The original concept for Ghost Song was created using Stencyl 3.x
Pro Great performance on every platform
Stencyl exports your games to native code so they have great performance on every platform.
Pro Cache as bitmap
Automatically detects changes and updates bitmap cache. Allows to gain even more performance on heavy scenes and runs smoothly on old devices.
Pro Most valuable when size matters
All engine code is written in ES6, fully GCC typed, allowing to eliminate all dead code from your app.
Pro Advanced scene graph and rendering pipeline
Dirty flag tracks scene changes and avoids unnecessary calculations and context calls. If no changes were made to the scene since last frame, no rendering will be done. Battery efficient.
Pro Good performance
According to the tests on the Github page, the performance is better than in Phaser!
Pro Good and clear source code
The source code is well commented and easy to understand.
Pro Super small build size
Super small build size through dead code elimination. The best for playable ads and Facebook Instant Games.
Cons
Con Not a powerful engine
Should be used for basic games only.

Con Only available via subscription
There should be an option to buy it outright, especially considering it is written by a one man team....this is not exactly an Adobe level enterprise with shareholders, so there is no excuse!
Con Slow release cycle
Con Updated
It needs much to improve for mobile games, it was left in the era of Flash games. In Android you can not even put the native keyboard, you can not access things like native camera, GPS or native text input.
Con Tile system is somewhat inflexible
Con Small community
The project is young, so the community is extremely small.
