Because Steam doesn't allow more than two Game Collector showcases yet for some reason.

Deep Rock Galactic
Warhammer: Vermintide 2

Armello

Killer Instinct (2013)
MultiVersus ((RIP?) Doubling the XP needed to level up characters killed the game, among other things)
Valheim
Hunt: Showdown
Sea of Thieves
No Man's Sky (on GOG)
Dead by Daylight
Grim Dawn
Monster Hunter World: Iceborne
Old School RuneScape
Dragon Ball FighterZ
Street Fighter V
Killing Floor 2
Blacklight: Retribution (RIP)
Awesomenauts
PAYDAY 2
Guild Wars 2
Torchlight II
Dota 2
Payday: The Heist
Terraria
Left 4 Dead
Killing Floor
Sid Meier's Civilization V
Battlefield: Bad Company 2
Street Fighter IV
Shattered Horizon (RIP)
Left 4 Dead 2
Company of Heroes
Team Fortress 2
Battlefield 2
Age of Empires II