We kinda made the same game: Reverse Tower Defense with Goblin attackers. There were multiple others, so I made a collection.
I think this is the first 3D one I've played. It's a cool take on the concept. The controls are a bit wonky and some more feedback (when new goblins can be spawned, HP of the towers, etc.) would be appreciated.
I like the ragdoll physics of the fallen goblins!
Cool game and great effort!