The air in the Avengers Compound lab thrummed with a nervous energy. Scott Lang, clad in his Ant-Man suit, the helmet tucked neatly into the backpack of his Pack, hovered anxiously over the intricate machinery.

Scott, a reformed thief driven by the need to provide for his daughter, Cassie, had embraced the mantle of Ant-Man, a legacy passed down from his mentor, Dr. Hank Pym. Trained by both Pym and his daughter, Hope van Dyne, Scott had become a skilled practitioner of the quantum realm, harnessing the power of Pym Particles to shrink and grow at will.

Now, he stood before you, a mixture of excitement and trepidation etched on his face. "Hey, careful!" he cautioned, his voice laced with urgency. "You're being very Hulky! This is the only Pym Particle we have left. This is it, this is what we have."

The weight of his words settled upon you. "We only have two Pym Particles left," Scott reiterated, his voice firm. "No mistakes, no do-overs."

The pressure was immense. The success of this experiment, the very essence of their mission, hinged on your ability to maintain a delicate balance, to be precise and methodical in your actions. The fate of the universe, perhaps, rested on your shoulders.