Games like The Relentless
Games like The Relentless include Project Wingman, Timberman, Timberman VS, Cyberhunt, and Snakeybus. We matched them by the tags players give The Relentless on Steam (Action, Indie, Casual, and Arcade): closest matches first, and among equally close ones the better-known games.

Project Wingman
Shared: Action · Indie · Arcade

Timberman
Shared: Casual · Indie · Action

Timberman VS
Shared: Action · Casual · Indie

Cyberhunt
Shared: Action · Indie · Casual

Snakeybus
Shared: Indie · Action · Casual

One Finger Death Punch 2
Shared: Action · Indie · Casual

Vampire Survivors
Shared: Indie · Casual · Action

Retrowave
Shared: Indie · Casual · Action

Jet Island
Shared: Action · VR · Indie

Superflight
Shared: Indie · Casual · Action

UFO 50
Shared: Indie · Action · Arcade

Streets of Rage 4
Shared: Action · Indie · Arcade

One Finger Death Punch
Shared: Action · Indie · Casual

Contractors
Shared: Action · VR · Indie

BOXVR
Shared: Indie · Action · Casual

Trip to Vinelands
Shared: Action · Indie · Arcade

Megabonk
Shared: Indie · Action · Arcade

Zuma's Revenge!
Shared: Action · Casual · Arcade

New Retro Arcade: Neon
Shared: VR · Casual · Indie

Pistol Whip
Shared: Action · VR · Arcade

Spin Rhythm XD
Shared: Casual · Indie · Action

Rogue Legacy 2
Shared: Action · Arcade · Indie

A Dance of Fire and Ice
Shared: Indie · Arcade · Casual

Sixtar Gate: STARTRAIL
Shared: Action · Casual · Arcade