Games like Synthrun
Games like Synthrun include Pseudoregalia, Neon White, Clustertruck, A Story About My Uncle, and Haste. We matched them by the tags players give Synthrun on Steam (3D Platformer, Parkour, Abstract, Platformer, and Indie): closest matches first, and among equally close ones the better-known games.

Pseudoregalia
Shared: 3D Platformer · Parkour · Platformer

Neon White
Shared: 3D Platformer · Parkour · Platformer

Clustertruck
Shared: Parkour · 3D Platformer · Action

A Story About My Uncle
Shared: Parkour · Indie · 3D Platformer

Haste
Shared: Parkour · 3D Platformer · Action

Refunct
Shared: 3D Platformer · Parkour · Platformer

Sonic Adventure DX
Shared: 3D Platformer · Platformer · Action

Prince of Persia: The Forgotten Sands™
Shared: Parkour · Platformer · Action

Sonic Adventure 2
Shared: 3D Platformer · Platformer · Action

VHOLUME
Shared: Parkour · 3D Platformer · Platformer

Pumpkin Jack
Shared: 3D Platformer · Action · Indie

Cyber Hook
Shared: 3D Platformer · Parkour · Indie

Sonic Lost World
Shared: 3D Platformer · Platformer · Parkour

Only Up: With Friends
Shared: Parkour · 3D Platformer · Casual

Sonic Frontiers
Shared: 3D Platformer · Action · Platformer

My Friend Pedro
Shared: Parkour · Indie · Action

Hover
Shared: Parkour · Action · 3D Platformer

Kao the Kangaroo: Round 2 (2003 re-release)
Shared: 3D Platformer · Platformer · Action

Prince of Persia®: The Sands of Time
Shared: Parkour · Platformer · Action

Last Train Outta' Wormtown
Shared: 3D Platformer · Platformer · Action

SONIC X SHADOW GENERATIONS
Shared: 3D Platformer · Action · Platformer

Crash Bandicoot™ 4: It’s About Time
Shared: 3D Platformer · Platformer · Action

Mirror's Edge™
Shared: Parkour · 3D Platformer · Platformer

Bomb Rush Cyberfunk
Shared: 3D Platformer · Parkour · Action