He is trying to catch the Moby Dollar at his Dream Ocean. When SpongeBob comes to his dream, Mr. Krabs tells him to take his big wallet and add the Moby Dollar, that he caught, inside of it. However, SpongeBob accidentally lets the wallet fall into the sea and Mr. Krabs ties him up with a rope tied to a plunger sticking out of a gun and fires it, along with SpongeBob still on it.
He appears in a daydream/flashback when SpongeBob tells Plankton the story of when the real Mr. Krabs told him the formula. In this daydream, Mr. Krabs calls SpongeBob to his office to tell him the formula, but instead tells him to follow him in a giant circle across the ocean (to ensure they aren't being followed). Before he can tell SpongeBob the formula, Plankton interrupts to prepare his pen, alerting Mr. Krabs in the daydream, causing him to grab Plankton, curl him into a ball, and fling him away.
Shubie asks to watch King Neptune eat during his party, which is being held at the Krusty Krab. At first, Mr. Krabs finds it weird and wonders why he would let her do that, but Daydream Mr. Krabs appears with a hammer with a dollar sign on it and wacks Mr. Krabs with it, indicating that he can make money off of the opportunity.