I’m making a 2d game. The whole map, including the ladders, is part of one sprite. I want to enable vertical movement where the ladders are only. How do I do this?

I’m guessing you want something like Donkey Kong, right?

Try this: public class ClimbLadder : MonoBehaviour
{

 public Transform ladder1;
 public Transform ladder2;
 //etc...

 public bool atLadder1 = false;
 public bool atLadder2 = false;
 //etc...

 float laddercheckRadius = (somewhere around 3f);

 void Update () {
      atLadder1 = Physics2D.OverlapArea ([Parameters][2]);
      atLadder2 = Physics2D.OverlapArea (Parameters);
      //etc...

      if (Input.GetButtonDown ("your climb button") && atLadder1)
           //Whatever function you want to use to climb
 }

}

It should work something like this, sorry I wasn’t able to put full focus into it. ladder1, 2 and so on will be empty gameObjects placed on the ladders. This code goes on the player, and needs some Collider2D on it. Hmu if it doesn’t work, I’ll try to test it for myself.