Automatic Wool Farm

Sheep regrow wool over time by eating grass blocks, turning the grass beneath them to dirt in the process. That's the whole mechanic this farm automates: pen a sheep over grass, let it eat, shear it repeatedly, and you never need to breed more sheep.

A dispenser loaded with shears and aimed at a penned sheep will shear it exactly like a player would when triggered by redstone, dropping 1 to 3 wool blocks straight to a hopper below. That's the unit you repeat once per color for a full rainbow build, each sheep in its own small pen so the dispenser's aim can't miss.

Since sheep actually need to eat grass to regrow wool, the pen floor needs real grass area, or some way to let eaten dirt patches revert back over time. A pen that's too small or entirely stone-floored will shear once and then sit idle until the grass comes back, which is the most common reason a first attempt seems to die after the initial haul.

Timing the shear trigger is a balance. Too often and you're wasting activations on sheep that haven't regrown anything yet. Too rare and you're leaving full fleeces sitting unused. A slow clock, or honestly just a button you press when passing by, both work fine since regrowth isn't fast to begin with.

A full 16-color setup needs one sheep of each dye color, either dyed directly or bred from parents (offspring inherit a parent's color, sometimes a blend if the parents differ). Once it's running, wool stops being something worth spending dye on repeatedly.