Games like Only Up! 1
Games like Only Up! 1 include Chained Together, Mount & Blade II: Bannerlord, Only Up !, Totally Accurate Battle Simulator, and Mount & Blade: Warband. We matched them by the tags players give Only Up! 1 on Steam (Adventure, Strategy, Casual, Platformer, and Exploration): closest matches first, and among equally close ones the better-known games.

Chained Together
Shared: Adventure · Casual · Platformer

Mount & Blade II: Bannerlord
Shared: Strategy · Medieval · Adventure

Only Up !
Shared: Adventure · Strategy · Casual

Totally Accurate Battle Simulator
Shared: Strategy · Adventure · Realistic

Mount & Blade: Warband
Shared: Strategy · Adventure · Medieval

BEEP
Shared: Adventure · Platformer · Indie

FEZ
Shared: Platformer · Adventure · Exploration

Hollow Knight
Shared: Platformer · Adventure · Exploration

A Short Hike
Shared: Adventure · Exploration · Casual

Plague Inc: Evolved
Shared: Strategy · Casual · Indie

Kingdom Come: Deliverance
Shared: Adventure · Realistic · Medieval

Slime Rancher
Shared: Adventure · Exploration · Casual

Grow Up
Shared: Adventure · Casual · Exploration

PEAK
Shared: Adventure · Exploration · Physics

Grow Home
Shared: Adventure · Exploration · Casual

A Story About My Uncle
Shared: Adventure · Platformer · Indie

DAVE THE DIVER
Shared: Adventure · Casual · Exploration

Hollow Knight: Silksong
Shared: Platformer · Indie · Adventure

Landfall Archives
Shared: Casual · Strategy · Singleplayer

A Hat in Time
Shared: 3D Platformer · Adventure · Platformer

Drifter Star: Evolution
Shared: Casual · Strategy · Adventure

Yooka-Laylee
Shared: Adventure · 3D Platformer · Platformer

ALTF4
Shared: 3D Platformer · Platformer · Casual

The Basement Collection
Shared: Adventure · Strategy · Platformer