How do I incapacitate the queen monster?

Hint 1 of 8:

Drug her!

Hint 2 of 8:

Use an ingredient you've used before for this purpose

Hint 3 of 8:

Mix a potion with the digitalis

Hint 4 of 8:

Mix the potion in the basin

Hint 5 of 8:

Use something to redirect the water supply

Hint 6 of 8:

Use the copper pipe on the water supply