"Push faster you retards!" Cartman said at Phineas and Ferb.

"Hey Ferb, why don't we head out?" Phineas asked.

Ferb shrugged as he grabbed the ice cream from Cartman. Phineas and Ferb then ran without pushing the cart. "Come back here!" Cartman ordered.

Grim, Billy and Mandy were walking down the aisle. "Why did I have to come here!?" Grim asked annoyed.

"Because Mandy and I can't reach the tops shelves?" Billy said.

"And your parents couldn't have taken you?" Grim asked.

"But they are busy" Mandy said. "You better not forget to get the ice cream"

Phineas and Ferb then ran into Billy, dropping the ice cream. "Look out Ferb! It's the Grim Reaper!" Phineas said as he and his step brother backed up.

"Billy, put the ice cream away" Mandy ordered.

At this time, Rainbow, Pinkie, Zim, Mojo, Shaggy and Scooby had caught up to them. "It's the Grim Reaper!" Shaggy said as he and Scooby grabbed each other in fear.

"Get out of the way, Zim must get the last ice cream!" Zim demanded.

Billy looked at Zim confused. "Why does that guy sound like me?" Billy asked.

"I am keeping the ice cream" Mandy said getting in the faces of the others. "Grim, you better hold them off!"

Mandy grabbed Billy and began to run. "Alrighty mon, none of you will be getting past me!" Grim said as he pulled his scythe out. Shaggy and Scooby ran past him screaming.

Rainbow charged as she dashed at Grim. "You are not getting away with it!" She ripped one of the arms out.

Pinkie bounced past Grim. Mojo, Zim and Rainbow followed her trying to catch up to Billy and Mandy. Phineas and Ferb looked at Grim, "Ferb, I am quite curious on how a skellington is able to hold himself up with only bones"

Cartman growled as Grim's arm landed on him. "Am I going to paddle?" Cartman asked. "Great, I have to do everything for myself"

Billy and Mandy were running down the aisle. Rainbow Dash flew above them, grabbing the ice cream.

She then crashed into a shelf, causing cans of soup to fall on her and along with Dipper and Mabel. "Great Mabel, did you see the journal?" Dipper asked digging out Rainbow Dash. SHe then picked up the ice cream. "Thank you for getting us the ice cream"

"We didn't bring the journal" Mabel pointed out.

"Good point" Dipper said.

Mojo, Zim, Shaggy, Scooby, Billy, Mandy and Pinkie all jumped into the cans looking for the ice cream. "Where is it!?" Pinkie asked.

"How should I know!?" Zim asked.

"Mabel, I think we should run" Dipper said before they try to kill us. He grabbed his sister by the arm and dragged her away before the others saw them.

And it looks like the Grim Reaper and the Pines twins have gotten involved.

Credit

Mojo Jojo- Powerpuff Girls
Zim- Invader Zim
Scooby and Shaggy- Scooby Doo
Rainbow Dash and Pinkie Pie- My Little Pony: Friendship is Magic
Eric Cartman- South Park
Phineas and Ferb- Phineas and Ferb
Billy, Mandy and Grim- The Grim Adventures Of Billy and Mandy
Dipper and Mabel- Gravity Falls