I have a 2×2 vertical water shaft I used for transporting hostile mobs.
At the top of the shaft I want the water to flow horizontally so the mobs are transported into my mob harvester.
Placing water blocks directly above the shaft causes the water to flow down.
How do I place water in a way the will horizontally push the hostile mobs off the top of the shaft?
Best Answer
Place the water sources above some signs. Although they don't have a collision box (can't block mobs), signs block water from flowing in that direction.
This is working because in Minecraft pretty much anything is a block. This includes water and signs (although you can look through them). Water won't flow through any block as that would require to interfere with it. Therefore this also works with ladders, fences, steps, etc.
The signs also keep the mobs from drowning.