Games like HordeCore
Games like HordeCore include Megabonk, Vampire Survivors, Brotato, Soulstone Survivors, and Yet Another Zombie Survivors. We matched them by the tags players give HordeCore on Steam (Bullet Heaven, Action Roguelike, Bullet Hell, Roguelite, and 2.5D): closest matches first, and among equally close ones the better-known games.

Megabonk
Shared: Bullet Heaven · Action Roguelike · Roguelite

Vampire Survivors
Shared: Action Roguelike · Bullet Hell · Roguelite

Brotato
Shared: Bullet Hell · Action Roguelike · Bullet Heaven

Soulstone Survivors
Shared: Bullet Heaven · Action Roguelike · Bullet Hell

Yet Another Zombie Survivors
Shared: Bullet Heaven · Action Roguelike · Roguelite

Halls of Torment
Shared: Action Roguelike · Bullet Hell · Roguelite

Death Must Die
Shared: Action Roguelike · Bullet Hell · Roguelite

Hades
Shared: Action Roguelike · Roguelite · Indie

Rogue: Genesia
Shared: Bullet Heaven · Action Roguelike · Bullet Hell

Boneraiser Minions
Shared: Action Roguelike · Bullet Hell · Roguelite

BALL x PIT
Shared: Roguelite · Bullet Hell · Action Roguelike

Tower of Babel: Survivors of Chaos
Shared: Bullet Heaven · Action Roguelike · Bullet Hell

Deep Rock Galactic: Survivor
Shared: Action Roguelike · Bullet Heaven · Roguelite

The Spell Brigade
Shared: Bullet Heaven · Bullet Hell · Roguelite

Enter the Gungeon
Shared: Action Roguelike · Bullet Hell · Roguelike

20 Minutes Till Dawn
Shared: Action Roguelike · Bullet Hell · Roguelite

Nova Drift
Shared: Bullet Hell · Roguelite · Action Roguelike

Nordic Ashes: Survivors of Ragnarok
Shared: Bullet Heaven · Action Roguelike · Bullet Hell

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

Noobs Want to Live
Shared: Bullet Hell · Action Roguelike · 2.5D

Rogue Legacy
Shared: Action Roguelike · Indie · Roguelike

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

Astro Prospector
Shared: Action Roguelike · Roguelite · Bullet Heaven

Nuclear Throne
Shared: Action Roguelike · Bullet Hell · Indie