Games like M.A.S.S. Builder
Games like M.A.S.S. Builder include ARMORED CORE™ VI FIRES OF RUBICON™, DAEMON X MACHINA, GUNDAM BREAKER 4, SD GUNDAM BATTLE ALLIANCE, and Warframe. We matched them by the tags players give M.A.S.S. Builder on Steam (Mechs, Action RPG, Character Customization, Robots, and Gun Customization): closest matches first, and among equally close ones the better-known games.

ARMORED CORE™ VI FIRES OF RUBICON™
Shared: Mechs · Character Customization · Robots

DAEMON X MACHINA
Shared: Mechs · Character Customization · Robots

GUNDAM BREAKER 4
Shared: Mechs · Robots · Action RPG

SD GUNDAM BATTLE ALLIANCE
Shared: Mechs · Action RPG · Robots

Warframe
Shared: Action RPG · Character Customization · Action

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

Mecha BREAK
Shared: Mechs · Robots · Character Customization

Titanfall® 2
Shared: Mechs · Shooter · Sci-fi

BattleTech
Shared: Mechs · Robots · Sci-fi

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

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

Path of Exile
Shared: Action RPG · Hack and Slash · Character Customization

CODE VEIN
Shared: Character Customization · Action RPG · Anime

Dolls Nest
Shared: Mechs · Character Customization · Robots

Mass Effect™ Legendary Edition
Shared: Character Customization · Sci-fi · Action RPG

Granblue Fantasy: Relink
Shared: Action RPG · Hack and Slash · Anime

MONSTER HUNTER RISE
Shared: Character Customization · Action RPG · Action

Monster Hunter: World
Shared: Character Customization · Action RPG · Action

MOBILE SUIT GUNDAM SEED BATTLE DESTINY REMASTERED
Shared: Mechs · Action RPG · Robots

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

GOD EATER 3
Shared: Character Customization · Anime · Hack and Slash

Sands of Salzaar
Shared: Indie · Character Customization · Action RPG

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

BREAK ARTS II
Shared: Mechs · Robots · Character Customization