Having trouble with player following mouse

So the code I wrote is technically “working” its just, no matter how much I mess with the MouseX sensitivity, it just doesnt follow the mouse right.

using UnityEngine;
using System.Collections;

public class MouseRotation : MonoBehaviour

    void Update()
        float mouseInput = Input.GetAxis("Mouse X");
        Vector3 lookhere = new Vector3(0, mouseInput, 0);

The camera is a top down camera overlooking an “arena.” I already have another script for basic WASD movement. This script I felt would be for an easy mouse rotation. If you were to picture it, the camera points on the “field” overlooking the player. When you move the mouse in the top half of the “circle” above the character the character will somewhat follow it, but once you put the mouse below the player on the field its almost as if the character is inverted and looks above again. Any input would be appreciated!

Try using ScreenPointToRay from your current mouse position. It casts a ray “through the screen” onto your scene. If you setup your collision layers in a way that the ray only hits the terrain, you can make your character look towards the point using transform.LookAt(ray.hit.point).

This would look something like this:

Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
RaycastHit hit;
if(Physics.Raycast(ray, out hit, Mathf.Infinity)) {

For more explanation see Unity - Scripting API: Physics.Raycast