You can change your skin in the Main Menu or the Pause Menu under the "Customization" or "Codex" tab.
Most skins are tied to specific achievements, such as: Beating certain boss encounters. Completing the game on various difficulty settings. Earning "Par" times on levels. tinertia-codex-update-v2-0-gauntlet-mode-and-skins
Familiarize yourself with the end-of-level portals to maintain your speed as you spawn into the next stage. You can change your skin in the Main
Remember that rocket jumping off walls provides more horizontal push, while jumping off the floor gives you maximum verticality. 🎨 New Skins & Customization continuous run [1].
Complete every level in the game (over 70 stages) in a single, continuous run [1].