Serious Engine 3 is the next version of the Serious Engine. It is less of a dramatic upgrade than the changes from Serious Engine 1 to Serious Engine 2 were, but there are still some noticeable improvements, such as better lighting. For modders, a new scripting language has been added for them to learn.
Unlike previous Serious Engine versions, it seems that Serious Engine 3 cannot be licensed. This might be because of a lack of interest thanks to Epic Games cornering the engine licensing business.
Serious Engine 3 uses Serious Editor 3 as its editor. Serious Editor 3 is much less of a dramatic change when compared to the difference between Serious Editor 1 and Serious Editor 2. In fact, it's layout is pretty much the same as Serious Editor 2's.
Serious Engine 3 was first shown off in a Croatian video game magazine in 2006. The magazine showed off the screenshots of Croteam's canceled Unnamed Military Shooter, a picture showing an early Canned Cain and Khnum and a screenshot showing an Albino Cyclops and a few Zombie Soldiers attack Serious Sam in a ruined middle eastern town. This was a mockup for what Serious Sam 3: BFE would look like.
- Proper HDR support.
- Better lighting, which allows for more realistic lights in levels.
- Increased polygon count limit for models, which allows for even more detailed and complex models than what's been allowed before.
- A new scripting language, LUA, has been added to replace Serious Engine 2's Macro. This was most likely because it's more flexible or because it's easier to learn and/or use.
- Better shadows, to go along with the improved lighting.
- Greatly improved weather effects.
- Water surface physics for more realistic object interaction with water.
- Bump mapping for more detailed texture surfaces.
- Improved netcode for smoother online play that also takes advantage of modern internet connections like broadband.