Hoo hoo hoo! He had found plenty of grape and apple candies in one of the cafeteria’s vending machines, as well as a small personal sized tub of chocolate ice cream. And to wash it down, a can of grape soda. He would admit, it was a bit of luck that he was able to find those particular things in the cafeteria, but as the old saying goes, never look a gift horse in the mouth.
With the groceries in a makeshift back, Joker started walking back towards the vaults. Along the way, he passed a chemistry lab. “Fortune smiles on the clown! Goodie goodie goodie!” He jumped on one foot and then the other out of excitement before running towards the lab, throwing open the door and taking inventory of what he saw in there. It was almost a plethora of mind controlling substances. Well, that made sense, seeing as how Aperture would have to control the test subjects some how.
"Oh oh oh! Which one which one do I use?!" He could barely contain himself as he grabbed a vial marked Lysergic acid diethylamide. "That’s LSD for you playing along at home!" he said over his shoulder. He followed up that by grabbing a vial of Scopolamine, which was a powerful hallucinogen and mind control drug. Mixed in the proper way, the two combined would form a powerful poison that would put Lydia under his total control.
Grabbing a few tools, Joker mixed the two drugs into a very thin liquid in a pot. Once everything was ready, he opened up the candies and sloshed them around in the liquid, making sure they were well coated. Using a set of tongs, he pulled the candies out. The gummies were coated nicely. He slipped them back into the back from whence they came and then opened up the ice cream. He poured the liquid into the ice cream and used the same tongs he had used on the candy, he made sure that the liquid was well mixed into the ice cream itself.
His labors done, he resealed the ice cream and set the items back in his bag. He left the lab and started walking back towards the vaults. A few minutes later, he opened up the door to Harpy’s vault, where Lydia had been waiting, and walked up to her.
"Let it never be said that Joker isn’t a man of his word!" he proudly proclaimed as he dumped the items from the bag onto Harpy’s bed. "Dig in kid! And once you’re done, we’ll go over how to bring smiles to the faces of everybody in Aperture!"