Or maybe i should have made it more clear in game. Do you have any recommendations to do so? My thoughts were: At the beginning you are all faced with enemies around you. These enemies can only be killed by colliding into them. So my plan was that if the player is all sorrounded by them the first instinct is to shoot but the bullet does not kill the enemy but bouncing into them kills does. When enemies respawn the bullets blink the color of the enemy to indicate which enemy and to highlight that the bullets create the enemies. One factor which is not as visible might be that the respawns is a percentage of the static bullets and that enemies increase in speed over time so that it will not be like playing COD Zombies. Was it clear that bouncing into bullets give one point and full health? And that you can cancel respawns be destroying the bullets? 

Okay. Thank you very much. The goal is to collect the bullets you have shot. When collecting a bullet you get full health and a point. Do you have an alternative way or an idea to express this better? :)

Thanks very much. Did you also notice that when you healed you got a point? :)