Here's the team members of Horned King's Dark Army :

Leader : Horned King

Co-Leader : Bowser

Members of the team (Generals) :

The generals : Bowser Jr, Dr. Eggman, Zeno and Dufort (Zatch Bell), Algernon (Bully), Clockwerk, Sir Raleigh, Muggshot and General Tsao (Sly Cooper), Cell and Frieza (Dragon Ball Z), Dogen (Senran Kagura), Chase Young, Jack Spicer and Wuya (Shaolin Showdown), Itachi Uchiha (Naruto), Bill Cipher and Gideon Gleeful (Gravity Falls).

Kirby (video game): King Dedede and Escargoon.

Pokemon: Shamus, Ghetsis and Lysandre.

Naruto: Orochimaru

Spyro the Dragon: Gnasty Gnorc.

The Owl House: Lilith, Boscha, Emperor Belos and Hunter.

Pac-Man and the Ghostly Adventures: Dr. Buttocks and Buttler

Billy Hatcher: Dark Raven

Spongebob Squarepants: Plankton

My Little Pony Friendship is Magic: Cozy Glow, Lord Tirek, Queen Chrysalis and King Sombra

Neopia: Geraldina

Shrek: Prince Charming

RWBY: Salem and Cinder Falls

Fairy Tail: Zeref

Madagascar: Capitaine Chantal Dubois.

Jak and Daxter: Baron Praxis

Undertale: Asgore

Mortal Kombat: Kronika

Castlevania: Count Dracula

MLATR: Vexus

Resident Evil: Albert Wesker and Nemesis

How to Train your Dragon: Drago

Rayman: Admiral Razorbeard

God of War: Zeus (God of War 3)

Rogue Galaxy: Valkog Drazer

Kim Possible: Dr Drakken

Samuraï Jack: Aku

Star vs the forces of evil: Toffee

Danny Phantom: Vlad

Persona 5: Masayoshi Shido, Kamoshida and Sugimura

Over the Edge: Verminator and Gladys

Black Clover: Patolli

Bully: Gary

7even DeadlySins: Demon King

My Hero Academia: Tomura Shigaraki, All for one and League of villains.

The rising of the Shield Hero: Malty "Bitch" Melromac

Rugrats/All grown up: Coco Labouche and Jean-Claude

Captain Underpants: Professor Poopypants and Melvin Sneedly

Mario: Wingo

Fire Emblem: Validar

Animaniacs: Thaddeus Plotz, Nora Rita Norita, Pinky and Brain