Games like Hopeless Days
Games like Hopeless Days include Vampire Survivors, Megabonk, 20 Minutes Till Dawn, Black Myth: Wukong, and God Of Weapons. We matched them by the tags players give Hopeless Days on Steam (Action, Casual, Bullet Hell, Roguelite, and Combat): closest matches first, and among equally close ones the better-known games.

Vampire Survivors
Shared: Bullet Hell · Roguelite · Casual

Megabonk
Shared: Roguelite · Bullet Hell · Action

20 Minutes Till Dawn
Shared: Bullet Hell · Roguelite · Survival

Black Myth: Wukong
Shared: Action · Combat · RPG

God Of Weapons
Shared: Roguelite · Bullet Hell · Casual

Death Must Die
Shared: Bullet Hell · Roguelite · Action

FatalZone
Shared: Bullet Hell · Roguelite · Action

Left 4 Dead 2
Shared: Action · Zombies · Shooter

The Last Stand: Aftermath
Shared: Zombies · Roguelite · Survival

Yet Another Zombie Survivors
Shared: Roguelite · Zombies · Indie

Noobs Want to Live
Shared: Bullet Hell · Action · Casual

Pass the Fear
Shared: Roguelite · Bullet Hell · Action

Halls of Torment
Shared: Bullet Hell · Roguelite · Action

BALL x PIT
Shared: Action · Roguelite · Bullet Hell

Deep Rock Galactic: Survivor
Shared: Roguelite · Bullet Hell · PvE

Brotato
Shared: Bullet Hell · Roguelite · Survival

Back 4 Blood
Shared: Zombies · Action · Shooter

Monsters are Coming!
Shared: Action · Roguelite · Bullet Hell

Goobies
Shared: Bullet Hell · Roguelite · Casual

Hades
Shared: Roguelite · Action · Indie

Arms of God
Shared: Bullet Hell · Action · Roguelite

Apocalypse Party
Shared: Casual · Bullet Hell · Roguelite

Dead Age
Shared: Casual · Zombies · Action

Soulstone Survivors
Shared: Bullet Hell · Roguelite · Action