This is a paid asset, but now you can download Fantasy Horde – Zombies Free.
Detail this asset from Unity Store: Original Link
Fantasy Horde – Zombie v1.2
FANTASY HORDE SERIES:
Highly optimized for mobile use or to create massive Hordes in your games!
It has an incredibly low polycount, optimized use of bones and no normal maps to work with simpler and lighter shaders.
Over 20 types of low poly Zombies ready to use in your game!
With this package you will get for free:
Perfect for your fantasy game and ready for Mecanim
Each model has low polygon counts and optimized textures.
The total polycount per model is around 1k tris.
These models use 512×512 textures (diffuse)
Includes 35 animations.
★ Highly optimized and clean meshes
★ Efficient UVs usage to allow higher quality with lower texture sizes
★ Minimized number of materials and meshes to allow lower draw calls and high performance
★ Top quality animations
★ Clean project without unnecessary files
URP and HDRP:
Polygonmaker packages work with URP and HDRP.
To convert our custom shader to URP or HDRP, please download Polygonmaker Shaders and unpack “Shaders URP” or “Shaders HDRP”
Change from Standard to Mobile Diffuse or Bumped depending of your budget.
Set the Max Size according your budget, for example 512 for third person games or 256 for RTS games.