When comparing Loom SDK vs Unity 2D, the Slant community recommends Unity 2D for most people. In the question“What are the best 2D game engines?” Unity 2D is ranked 7th while Loom SDK is ranked 45th. The most important reason people chose Unity 2D is:
2D game creation was a major feature request from the Unity community and was added with version 4.3. 2D is provided in both the Pro and Free distribution of Unity.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Live reload of code and assets across multiple platforms
Loom can live update changes in realtime, allowing you to see them on multiple devices immediately.
Pro Powerful command line workflow
Loom Turbo ($5/mo) gives access to powerful command line tools. For example, "loom new" to make a new project, "loom run" to run it. Packaging, deploy, and live reload are done automatically for you.
Pro Open source
The Loom runtime and LoomScript compiler are open source, with code available on GitHub, allowing you to have the freedom to fix the bugs and add the features your game needs.
Pro Examples
Loom includes over 30 examples ranging from complete sample games to demos of single features.
Pro Familiar and powerful scripting
Loom's scripting language is immediately familiar if you know JavaScript, ActionScript, TypeScript, C#, or Java. Internally, it uses a proven VM technology with over 10 years of heavy use in games.
Pro Good support
Loom devs are helpful.
Pro Cross-platform
Loom can deploy to Windows, OS X, Linux, iOS, Android (including Nook, Kindle Fire and Ouya). There are also custom port available for WP8, Blackberry and consoles.
Pro Built into Unity 4.3+
2D game creation was a major feature request from the Unity community and was added with version 4.3. 2D is provided in both the Pro and Free distribution of Unity.
Pro Integrates with Mecanim
Mecanim brings state machines and blending to 2D bone animation. The state machine editor allows for designers and programmers to visually create a Finite State Machine (FSM) to control when animations should play. Mecanim also allows for blending so an animation can transition smoothly between two states without the need of in between frames made by an animator.
Pro Sprite Sheet and Bone based animation supported
Both types of 2D animation for game development are supported in Unity’s system and can be used interchangeably in the timeline.
Pro Easily change sprites dynamically
Usually used for character customization, programmers can change any sprite in a bone animation at runtime easily by referencing the bone and loading the new sprite from the resources folder.
Cons
Con Documentation is lacking
Con No visual tools support
There's no level editor, asset viewer or any other visual tools in Loom SDK. Everything has to go through command line. I think it's fine if you really like typing.
Con Lacks critical features
- Vertices can't be animated, so you can't have ANY organic feel (like... lungs breathing).
- Parent bone can't be animated without affecting the children. This is especially impeding for organic feel, again.
- No option to show & unshow assets (or it is hidden), like for switching weapon on your character for exemple.

Con Poor script interface for texture atlases
Accessing individual sprites within an atlas texture is possible at runtime, but requires use of the Resources folder subsystem.
