Missing ward?

Awhile back riot was working on a ward where when you placed it, it would run to a location plant itself in the ground and alert you with a noise whenever an enemy champion was approaching even if the where invisible. I wanna know what happened to this it looked super amazing it was on the PBE for awhile then it just disappeared. I want this for a 4th trinket its so unique compared to the other 3 and to see how they would level it up when you hit lvl 9. I would like to see this in competitive play to see how the pros would use it ( if they even would).