Games like Outpost 3
Games like Outpost 3 include Vampire Survivors, Wall World, Death Must Die, Megabonk, and DAVE THE DIVER. We matched them by the tags players give Outpost 3 on Steam (Casual, Tower Defense, Roguelike, Bullet Hell, and Exploration): closest matches first, and among equally close ones the better-known games.

Vampire Survivors
Shared: Bullet Hell · Roguelite · Pixel Graphics

Wall World
Shared: Tower Defense · Roguelite · Roguelike

Death Must Die
Shared: Bullet Hell · Roguelite · Pixel Graphics

Megabonk
Shared: Roguelike · Bullet Hell · Roguelite

DAVE THE DIVER
Shared: Casual · Pixel Graphics · Exploration

Rocket Rats
Shared: Casual · Bullet Hell · Pixel Graphics

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

Dome Keeper
Shared: Roguelike · Tower Defense · Pixel Graphics

Seraph's Last Stand
Shared: Casual · Bullet Hell · Roguelike

Realm of the Mad God Exalt
Shared: Roguelike · Bullet Hell · Pixel Graphics

Balatro
Shared: Roguelike · Pixel Graphics · Casual

Wall World 2
Shared: Tower Defense · Roguelite · Roguelike

Halls of Torment
Shared: Bullet Hell · Roguelite · Roguelike

Boneraiser Minions
Shared: Bullet Hell · Roguelite · Pixel Graphics

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

Brotato
Shared: Roguelike · Bullet Hell · Roguelite

BALL x PIT
Shared: Bullet Hell · Roguelike · Roguelite

Necrosmith
Shared: Tower Defense · Bullet Hell · Roguelite

Dead Cells
Shared: Roguelike · Roguelite · 2D

Nordic Ashes: Survivors of Ragnarok
Shared: Bullet Hell · Exploration · Roguelike

Legend Creatures(传奇生物)
Shared: Exploration · Roguelike · Roguelite

Astro Prospector
Shared: Casual · Roguelike · Bullet Hell

Plants vs. Zombies GOTY Edition
Shared: Tower Defense · Casual · 2D

Asgard's Fall — Viking Survivors
Shared: Casual · Bullet Hell · Roguelite