Undo.PerformUndo  

static function PerformUndo () : void

Description

Perform an Undo operation.

This is similar to the user selecting Undo from the Edit menu.

See Also: PerformRedo.

Simple Scriptable Wizard that lets you perform an undo several times.

using UnityEngine;
using UnityEditor;

//Performs an Undo the number of times specified.

public class PerformVariousUndo : ScriptableWizard {
    public int numberOfSteps = 5;

    [MenuItem ("Example/Perform Various Undo %#u")]
    static void ExecuteMenu() {
        ScriptableWizard.DisplayWizard(
            "Perform various Undo at the same time",
            typeof(PerformVariousUndo),
            "Undo!");
    }

    void OnWizardCreate() {
        // We have to make this in order to make the undo
        // dont reset the value entered in the inspector
        int savedNumberOfSteps = numberOfSteps + 1;
        for(int i = 0; i < savedNumberOfSteps; i++) {
            Undo.PerformUndo();
        }
    }
}