Halfmilk RBA

Discovered by Cosmo & Kuwaga

Information

There's a rather bizarre oddity that can occur with Reverse Bottle Adventure.

When you empty the contents of a bottle, the bottle script will first check to see if there is a full bottle of milk (item value 26) in your inventory, rather than check what is on the pressed button. If there is a full bottle, a half-full bottle of milk (item value 31) will be put on both the button pressed and the inventory slot, regardless of the old bottle's contents.

This means that it's possible to use RBA write a "half-milk bottle" to B and the corresponding "inventory slot" (address) without using Bottle Adventure, but ONLY IF the target "inventory slot" already contains a "full milk bottle" (value 26).