You can replace the insects with 3d models
The easiest way to do it - replace art in existing enemies prefab: just go inside any enemy-prefab and
replace child object "planeUV" with your 3d-object.
For example (please also check attached screenshot):
1) In project window go to folder "Pizza_Defense\_Prefabs\_Insects\" and drag any enemy-prefab to
2) In Hierarchy window - expand object to get access to child object named "planeUV" ... and delete (or
3) Put any 3D model (prefab) instead of deleted "planeUV"
4) Select parent object (enemy-prefab) and put proper materials(related to new 3D object) to "EnemySkins"
and "DeadSkins" lists of Enemy script/component
5) Press "Apply" in Inspector window:
6) You can delete (or disable) the object/prefab from Hierarchy.