Games like Packmates
Games like Packmates include Megabonk, Brotato, Vampire Survivors, Death Must Die, and 20 Minutes Till Dawn. We matched them by the tags players give Packmates on Steam (Action Roguelike, Inventory Management, Online Co-Op, Bullet Heaven, and Singleplayer): closest matches first, and among equally close ones the better-known games.

Megabonk
Shared: Action Roguelike · Bullet Heaven · Survival

Brotato
Shared: Action Roguelike · Singleplayer · Bullet Heaven

Vampire Survivors
Shared: Action Roguelike · Bullet Hell · Pixel Graphics

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

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

Sephiria
Shared: Action Roguelike · Inventory Management · Roguelite

Halls of Torment
Shared: Action Roguelike · Pixel Graphics · Bullet Hell

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

The Spell Brigade
Shared: Online Co-Op · Bullet Heaven · Action Roguelike

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

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

Risk of Rain 2
Shared: Action Roguelike · Online Co-Op · Action

God Of Weapons
Shared: Action Roguelike · Inventory Management · Survival

Children of Morta
Shared: Action Roguelike · Online Co-Op · Pixel Graphics

ELDEN RING NIGHTREIGN
Shared: Online Co-Op · Singleplayer · Action

Boneraiser Minions
Shared: Action Roguelike · Bullet Heaven · Pixel Graphics

Streets of Rogue
Shared: Action Roguelike · Pixel Graphics · Roguelite

Ravenswatch
Shared: Action Roguelike · Online Co-Op · Action

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

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

Hades
Shared: Action Roguelike · Action · Roguelite

Gunfire Reborn
Shared: Online Co-Op · Action Roguelike · Roguelite

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

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