How to Customize a First-Person Controller in Unity: Adding Up and Down Movement

In this tutorial, I show how to customize a first-person controller in Unity so the player can move up and down using the Spacebar and Left Control keys. This is a practical movement-system modification where vertical input is added on top of an existing FPS controller, allowing the player to ascend and descend smoothly instead of being locked to ground-based movement. In this video, I cover: -Overview of the default first-person controller setup -Adding vertical movement input (Space & Left Ctrl) -Modifying the movement logic to support up and down motion -Preventing conflicts with existing jump or gravity logic -Testing the updated controller in a demo scene This approach is useful for flight systems, zero-gravity movement, noclip-style controllers, and experimental gameplay prototypes built in Unity.