Problem with minimap: render sprite just from top

Hi everybody!

I am developing a shooter and I’ve came up with a problem which has driven me mad for hours and I don’t know how to solve. I looked up the web since I think it’s something people must have faced before, but I can’t manage to find any solution to it, so I thought I should ask for help here!

So the problem is that I want to implement a minimap for the game, and to do so I followed this tutorial: https://www.youtube.com/watch?v=EQgmt20knLo . I managed to create the minimap succesfully, but I think this tutorial is focused on a single player game, since when it comes to making the minimap “tracker sprite” invisible for the player, it only enables “Owner No See”. The problem is that my shooter is multiplayer (right now it only works with some more-stupid-than-intelligent AI), and if I only enable this option I stop seeing my tracker but I still see those from the AI (as it can see in the attached picture).

I thought the solution would be creating a custom material for the sprite and messing up something there, but I have absolutely no knowledge about materials nor textures so I got really lost. What I would ideally like is to create a material that is rendered from the top view, but not from below. Is this possible in some way?

Thank you very much for your time!