Notes:

Here is the answer key/ list of mash up characters in the design:
1. Patrick Star (Spongebob Squarepants) as Starro the Conqueror
2. Jamie O Johanssen (Hey Arnold!) as Bloodsport
3. Powdered Toastman (Ren and Stimpy) as Peacemaker
4. Angelica Pickes (Rugrats) as Harley Quinn
5. Jorgen Von Strangle (Fairly Odd Parents) as Rick Flagg
6. Momo (Avatar: The Last Airbender) as bunny on Rick's shirt
7. Eliza Thornberry (The Wild Thornberrys) as Ratcatcher 2
8. (Catdog) as Sebastian
9. Quailman (Doug) as Polka Dot Man
10. Baby Shark (Baby Shark's Big Show) as King Shark/Nanaue
11. Skye's Ultimate Rescue Helicopter (Paw Patrol) as Task Force X helicopter
12. Miranda Killgallen (As Told By Ginger) as Amanda Waller
13. Prof. Calamitous (Jimmy Neutron) as The Thinker
14. Lars (Rocket Power) as Savant
15. Rocko (Rocko's Modern World) as Captain Boomerang
16. Dag (The Angry Beavers) as Weasel
17. Tak (Invader Zim) as Mongal
18. Johnny 13 (Danny Phantom) as Javelin
19. Krumm (Aaahh!!! Real Monsters) as TDK
20. Fanboy (Fanboy & Chum Chum) as Blackguard
21. Milton (Muppet Time) as Milton