Games like Astro Party EX - Stellar Upgrade
Games like Astro Party EX - Stellar Upgrade include Broforce, BALL x PIT, Hotline Miami, UFO 50, and Among Us. We matched them by the tags players give Astro Party EX - Stellar Upgrade on Steam (Top-Down Shooter, Action, Arcade, Party Game, and 2D): closest matches first, and among equally close ones the better-known games.

Broforce
Shared: Action · 2D · Pixel Graphics

BALL x PIT
Shared: Action · Arcade · Top-Down Shooter

Hotline Miami
Shared: Action · Top-Down · Pixel Graphics

UFO 50
Shared: Action · Arcade · Pixel Graphics

Among Us
Shared: 2D · Party Game · Space

Hotline Miami 2: Wrong Number
Shared: Action · Pixel Graphics · Top-Down

Apex Legends™
Shared: PvP · Action · Free to Play

Cyberhunt
Shared: Action · Arcade · Indie

Streets of Rage 4
Shared: Action · Arcade · 2D

Duck Game
Shared: Action · 2D · Pixel Graphics

Halo Infinite
Shared: Action · PvP · Free to Play

Pixel Gun 3D: PC Edition
Shared: PvP · Action · Pixel Graphics

THE FINALS
Shared: PvP · Action · Free to Play

Halo: Spartan Assault
Shared: Top-Down Shooter · Action · Top-Down

Terraria
Shared: 2D · Pixel Graphics · PvP

HELLDIVERS™ Dive Harder Edition
Shared: Top-Down Shooter · Action · Sci-fi

King Arthur's Gold
Shared: Action · 2D · Pixel Graphics

Vampire Survivors
Shared: 2D · Pixel Graphics · Action

Timberman
Shared: Action · Pixel Graphics · 2D

Rivals of Aether
Shared: Pixel Graphics · 2D · Indie

UBERMOSH Vol.3
Shared: Action · Arcade · Top-Down Shooter

Marvel Rivals
Shared: PvP · Action · Free to Play

Shovel Knight: Treasure Trove
Shared: Action · Pixel Graphics · 2D

RUNNING WITH RIFLES
Shared: Top-Down Shooter · Action · Top-Down