This may be due to the updated commands blocks in 1.9. This was made before the update and won't work with 1.9.
If you want to do it yourself this is basically the concept:
1. A repeating command block checks for an item in the world (the item used to spawn the turret)
2. Once the item is found it powers another command block that spawns an invisible snowman with slowness(so it doesn't move). Then immediately kills the item.
3. It also runs a set block command to set the block the snowman occupies to a brewing stand
3. A piston is powered and extends a Redstone block to a hopper clock that is set to wait a short while before switching and powering a command block to execute from the snowman a command to set the brewing stand block to air and kill itself.
I hope this helped!
Snowball Turret on October 31st, 2017 01:51 AM EST
