Games like Behold the Horde
Games like Behold the Horde include Megabonk, Crab Champions, Risk of Rain 2, Vampire Survivors, and Hades. We matched them by the tags players give Behold the Horde on Steam (Action, Casual, Roguelike, Action Roguelike, and Looter Shooter): closest matches first, and among equally close ones the better-known games.

Megabonk
Shared: Roguelike · Action Roguelike · Action

Crab Champions
Shared: Action Roguelike · Roguelike · Looter Shooter

Risk of Rain 2
Shared: Action Roguelike · Roguelike · Action

Vampire Survivors
Shared: Action Roguelike · Roguelike · Casual

Hades
Shared: Action Roguelike · Action · Roguelike

Skul: The Hero Slayer
Shared: Action · Action Roguelike · Roguelike

Wedding Witch
Shared: Action Roguelike · Action · Roguelike

The Binding of Isaac
Shared: Roguelike · Action Roguelike · Action

Slime Rancher
Shared: Cute · Casual · Colorful

Sephiria
Shared: Action Roguelike · Roguelike · Action

Gunfire Reborn
Shared: Roguelike · Action · Looter Shooter

Hades II
Shared: Action · Roguelike · Action Roguelike

Touhou Dystopian
Shared: Action · Action Roguelike · 3D

Juicy Realm
Shared: Action · Action Roguelike · Casual

The Binding of Isaac: Rebirth
Shared: Roguelike · Action Roguelike · Indie

Rogue Legacy
Shared: Roguelike · Action · Action Roguelike

Brotato
Shared: Roguelike · Action Roguelike · Singleplayer

Noobs Want to Live
Shared: Roguelike · Action · Casual

Rabbit and Steel
Shared: Action Roguelike · Roguelike · Cute

Risk of Rain (2013)
Shared: Roguelike · Action Roguelike · Action

Gang Beasts
Shared: Action · Casual · Funny

METALLIC CHILD
Shared: Action · Action Roguelike · Cute

Slime Rancher 2
Shared: Cute · Casual · Colorful

LORT
Shared: Action Roguelike · Roguelike · Looter Shooter