The level consists of 3 areas; there are 2 grounds which both have a mousehole on them, and a ball pool in the middle consisting of the remaining 3 blocks which appear to be skinny. There is cheese at the bottom of the pool.
This level is very hard to complete without the help of a shaman. But if you put some group effort to it, you can push the balls yourself and reach the cheese, wall jumping out and going into the right mousehole. Alternatively, you can practice wall jumping with cheese more on the left side and try to get into the left mouse hole.
You can spawn a couple of ghosted anvils or cannonballs (facing down) above the pool to force the balls out, and then build a bridge, trampoline, or box elevator out of the pool or let the mice wall jump their way to the hole, either on the left side, or on the right side.
Alternatively, spawn a couple of ghost big boxes in the middle of the pool to completely cover the middle of the pool and let the mouse get the cheese. After that, you can build a rotating anchor plank (N /J)to pull the mice out.
If you have the Nature's Return skill, you can use it to remove all of the balls.
Another solution is to make a ghost long plank. Anchor ghost long planks to each side of the already made ghost plank. Anchor balloons onto the plank. The airship you just made will take a lot of the balls out of the pin, with hopefully minimal lives lost.
A more humorous solution is to summon an ghosted version of Anvil god in the middle of the pool. Since the Anvil god is ghosted, it will only interact with the balls, thus clearing the pit very quickly. The mice will almost certainly be knocked about by the flying balls and sometimes out of the pit, thus finishing the level. Once the pit is cleared, you can finish up by means listed above.