Games like Spark Mk1
Games like Spark Mk1 include Vampire Survivors, PAC-MAN™ Championship Edition DX+, BALL x PIT, Planes, Bullets and Vodka, and Hotline Miami 2: Wrong Number. We matched them by the tags players give Spark Mk1 on Steam (Action, Arcade, 2D, Top-Down, and Pixel Graphics): closest matches first, and among equally close ones the better-known games.

Vampire Survivors
Shared: Pixel Graphics · 2D · Arcade

PAC-MAN™ Championship Edition DX+
Shared: Arcade · Action · 2D

BALL x PIT
Shared: Action · Arcade · Pixel Graphics

Planes, Bullets and Vodka
Shared: Action · Arcade · 2D

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

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

Warhammer 40,000: Boltgun
Shared: Action · Pixel Graphics · Retro

Shower With Your Dad Simulator 2015: Do You Still Shower With Your Dad
Shared: Arcade · 2D · Action

Broken Armor
Shared: Action · 2D · Pixel Graphics

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

UFO 50
Shared: Action · Pixel Graphics · 2D

Broforce
Shared: Action · 2D · Pixel Graphics

Orbt XL
Shared: Arcade · 2D · Action

SANABI
Shared: Action · Pixel Graphics · 2D

Timberman
Shared: Action · Pixel Graphics · 2D

METAL SLUG X
Shared: Action · Arcade · 2D

Cyberhunt
Shared: Action · Arcade · 2D

METAL SLUG
Shared: Action · Arcade · 2D

LUFTRAUSERS
Shared: Arcade · Action · 2D

Bloodstained: Curse of the Moon
Shared: Action · Pixel Graphics · 2D

Sonic Mania
Shared: 2D · Pixel Graphics · Action

Bit Blaster XL
Shared: Arcade · 2D · Action

Exit the Gungeon
Shared: Arcade · Action · 2D

ARCADE GAME SERIES: GALAGA
Shared: Action · Arcade · 2D