When comparing Rainbow vs ShiVa, the Slant community recommends Rainbow for most people. In the question“What are the best 2D game engines?” Rainbow is ranked 79th while ShiVa is ranked 92nd. The most important reason people chose Rainbow is:
Distributed under the MIT License.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Open source
Distributed under the MIT License.
Pro Written in modern C++, is scriptable in Lua
Pro Cross-platform
With support for Android, iOS, Linux, Mac OS X and Windows.
Pro Optional FMOD audio engine
Pro Supports Spine
Pro Physics
Box2D integrated with Lua bindings.


Pro Straightforward pricing with capable free option
The free ShiVa Web version is limited to web publication, but otherwise has the same capabilities as the $200 ShiVa Basic. Upgrading to the $1000 ShiVa Advanced brings tools geared toward team development and professional releases, such as integrated SVN support and profiling tools. All versions are royalty-free.

Pro Lua can be used for fast coding and C++ for optimization
All game logic can be scripted in Lua. ShiVa also provides a cross-compiler from Lua to C++, allowing Lua scripts to be further optimized and compiled to native code for performance.


Pro Great support
In addition to the help forum, Basic and Advanced licensees have chat and direct email access to the developers.
Pro Native c++ export
Pro C++ plugin development options

Pro Great performance on mobile
Smaller platform specific executables, native code export, good FPS even for complex scenes. ShiVa has great advanced optimization features, including PVS and LOD, decreasing number of drawcalls even in complex level. Platform specific profiles allow developers to customize size and compression level for textures and test those settings directly in editor. Other engine features, like lightning baking, mesh combining and GPU skinning will boost performance too.
Cons
Con Not as feature-rich as other engines
Con Small community
Being fairly new on the scene, there aren't much of a community to speak of.
Con ShiVa 2.0 has been worked on for nearly 4 years!
After 4 years of development and promises ShiVa 2.0 has JUST gotten into beta access.

Con Outdated
The current version 1.9.2 of ShiVa was released in December 2013. While there is active development on version 2.0, its beta is available only to paid licensees of the current version.
Con High Cost
Costs $200 for the basic version alone, which allows you to publish to any format other than web. The Team/Pro version costs $1000
