Monkey cubes (and others) can be broken by injecting them with substances other than water, in broken state, they cannot soak more water anymore.
Cubes can be repaired from being broken by taking a bite of them, possibly eating some of the injected substances in them.
Reproduction
unwrap monkey cube
inject monkey cube with potassium
splash monkey cube with water
Screenshots
Additional context
Although it makes sense that monkey cube can't soak water as its filled to the brim with other substance, it should at least be possible to see that monkey cube have been tampered with by upon inspection like "Cube is all soaked in some other substance".
Description
Monkey cubes (and others) can be broken by injecting them with substances other than water, in broken state, they cannot soak more water anymore.
Cubes can be repaired from being broken by taking a bite of them, possibly eating some of the injected substances in them.
Reproduction
Screenshots
Additional context Although it makes sense that monkey cube can't soak water as its filled to the brim with other substance, it should at least be possible to see that monkey cube have been tampered with by upon inspection like "Cube is all soaked in some other substance".