Ranked in these QuestionsQuestion Ranking
Pro Royalty free
You can use the engine for any commercial products and keep all the profits since NeoAxis does not ask for any royalties.
Pro Lot of maps and game-modes already built-in
Has about 30 built-in maps with different game modes which can be opened by the map editor and their source code can be edited.
Pro Completely free
Pro Good IDE support
Supports Visual Studio, SharpDevelop or MonoDevelop.
Pro Simple interface
You can learn how to use Neoaxis in a few days.
Pro Excellent visual tools, map editor and resource editor
You can easily create maps/scenes and add custom objects with physics and animations in a few minutes.
NeoAxis Engine is Windows-only.
Con Lack of tutorials
Unfortunately, the wiki doesn't contain much programming tutorials and the source code itself isn't much more self-documented. Creating new gamemodes or AI will require lot of investigations for beginners.