Gaia is a broad terrain creation, texturing, planting, population and general setup asset.

GeNa is a pure spawning asset that takes the spawning system to a whole new level. One of the key differences between Gaia and GeNa is that while Gaia is generically rule based, GeNa’s samples the environment you click on, and then selects 'like areas' area’s nearby in which to spawn your target objects. For example you can tell GeNa to only select areas plus or minus 5 meters in height from where you clicked. Fantastic for creating rock paths on a hill!

It’s an entirely new way to work and is incredibly intuitive. Another killer feature of GeNa is the lighting and spawn optimization system - it takes literally hours off your bake time while also improve lighting and frame rates.

Here is a summary of some of the key differences:

Sculpt terrain – Gaia YES, GeNa NO
Texture terrain – Gaia YES, GeNa no

Multi tiled terrain support - Gaia no, GeNa YES
Simple scene setup with water, player, wind and lighting – Gaia YES, GeNa no
Spawn grass, trees and prefabs on terrain – Gaia YES, GeNa YES
Spawn sophisticated collections of prefabs on terrain – Gaia YES, GeNa YES
Sophisticated image based masking – Gaia YES, GeNa YES
Sophisticated colour-map based masking – Gaia no, GeNa YES
Spawns on meshes – Gaia no, GeNa YES
Global and local spawning – Gaia no, GeNa YES
Click based spawn positioning – Gaia no, GeNa YES
Composable spawners – Gaia no, GeNa YES
Clickable spawn criteria configuration – Gaia no, GeNa YES
Real-time spawn criteria visualization – Gaia partial, GeNa YES
Automated prefab performance optimization – Gaia no, GeNa YES
Automated light probe placement and optimization – Gaia no, GeNa YES
Gravity based spawning system – Gaia no, GeNa YES
Fence and wall building system – Gaia no, GeNa YES
Fine grained spawn placement tuning – Gaia no, GeNa YES
Save and re-use spawners as prefabs – Gaia no, GeNa YES
Run-time spawning – Gaia – partial, GeNa YES

Another very powerful capability is the way in which a GeNa spawner can be configured and then saved as a prefab to be used at any time in the future. It can even be used to periodically spawn things are run time e.g. monstors, NPC's etc.

You can get GeNa from here.