I had considered to let Barbera play with the water first - slowly emptying the bottle right onto the floor. It would disrupt the focus on the tools that get a swift use at the end of this page. That realization of doom would have come the moment she emptied the water.
Also I doubt that Barbera is fully focussed and assessing the situation logically for the most pain she could cause. Toolbox, note from L, feeling groggy and pissed off - Barbera barely has the energy for funny games.