Games like RUTHLESS:1
Games like RUTHLESS:1 include Last Epoch, Wolcen: Lords of Mayhem, Path of Exile 2, Diablo® IV, and Grim Dawn. We matched them by the tags players give RUTHLESS:1 on Steam (RPG, Action RPG, Hack and Slash, Creature Collector, and Action): closest matches first, and among equally close ones the better-known games.

Last Epoch
Shared: Action RPG · RPG · Hack and Slash

Wolcen: Lords of Mayhem
Shared: Action RPG · Hack and Slash · RPG

Path of Exile 2
Shared: Action RPG · RPG · Hack and Slash

Diablo® IV
Shared: Action RPG · Hack and Slash · RPG

Grim Dawn
Shared: Action RPG · Hack and Slash · RPG

Black Myth: Wukong
Shared: Action RPG · RPG · Action

Warhammer 40,000: Inquisitor - Martyr
Shared: Action RPG · RPG · Hack and Slash

Minecraft Dungeons
Shared: Hack and Slash · RPG · Action RPG

Torchlight II
Shared: RPG · Action RPG · Hack and Slash

Torchlight III
Shared: RPG · Hack and Slash · Action RPG

UNDECEMBER: The Farside
Shared: RPG · Hack and Slash · Action RPG

Path of Exile
Shared: Action RPG · Hack and Slash · Loot

Weird RPG
Shared: RPG · Action RPG · Action

The Incredible Adventures of Van Helsing
Shared: RPG · Action RPG · Hack and Slash

The Slormancer
Shared: Hack and Slash · Action RPG · RPG

God of War
Shared: Action · RPG · Adventure

Minecraft Dungeons II
Shared: RPG · Action · Action RPG

God of War Ragnarök
Shared: RPG · Action · Hack and Slash

Victor Vran ARPG
Shared: Action RPG · RPG · Hack and Slash

Torchlight
Shared: RPG · Action RPG · Hack and Slash

No Rest for the Wicked
Shared: Action RPG · Hack and Slash · RPG

Diablo II: Resurrected – Infernal Edition
Shared: RPG · Action RPG · Hack and Slash

Stellar Blade™
Shared: Hack and Slash · Action · Action RPG

Titan Quest II
Shared: RPG · Action RPG · Hack and Slash