yeah you're right but using a circle uses less vertices than a Square pyramid since the circles are not meshes but just an image texture for a face of a cube. I did this while thinking of my game's future where there will be a mode which will have more bigger arena and more mobs who act like mobs from Megabonk (the mobs get on top of each other) while trying to catch the player). Also since this will be multiplayer and I'd like it if the players don't have to play a lagging game due to a lot of meshes on the screen.