Custom inspector popup for creating a item list

I'm trying to make a custom inspector to add items to my item list, and want to have popup menu's where I can just select attributes for the item. However when I select it on one it changes it on all of them.

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using System.Linq;
 using UnityEditor;
 
 
 [CustomEditor(typeof(CardManager))]
 internal class CardEditorInspector : Editor
 {
     bool showingDwarven = false;
 
     bool showingSet1 = false;
 
     public static string Common;
     public static string Uncommon;
     public static string Rare;
 
     public string[] currentRarity = new string[] { "Common", "Uncommon", "Rare" };
     public int RarityTypes = 0;
 
     public override void OnInspectorGUI()
     {
         CardManager cm = (CardManager)target;
 
         List<Dwarven> dwarven = new List<Dwarven>();
         for (int i = 0; i < cm.cardList.Count; i++)
         {
             if (cm.cardList[i].GetType() == typeof(Dwarven))
             {
                 dwarven.Add((Dwarven)cm.cardList[i]);
             }
 
             showingDwarven = EditorGUILayout.Foldout(showingDwarven, "Dwarven");
             if (showingDwarven == true)
             {
                 EditorGUI.indentLevel = 1;
                 showingSet1 = EditorGUILayout.Foldout(showingSet1, "Set 1");
                 if (showingSet1 == true)
                 {
                     EditorGUI.indentLevel = 1;
                     for (int i = 0; i < dwarven.Count; i++)
                     {
                         EditorGUILayout.BeginHorizontal();
                         EditorGUILayout.LabelField(dwarven[i].name);
 
                         if (GUILayout.Button("-"))
                             cm.cardList.Remove(dwarven[i]);
                         EditorGUILayout.EndHorizontal();
 
                         EditorGUI.indentLevel += 1;
                         dwarven[i].name = EditorGUILayout.TextField("Name: ", dwarven[i].name);
 
                         RarityTypes = EditorGUILayout.Popup(RarityTypes, currentRarity);
                         switch (RarityTypes)
                         {
                             case 0:
                                 dwarven[i].Rarity = Common;
                                 break;
                             case 1:
                                 dwarven[i].Rarity = Uncommon;
                                 break;
                             case 2:
                                 dwarven[i].Rarity = Rare;
                                 break;
                         }
 
                         dwarven[i].ID = int.Parse(EditorGUILayout.TextField("ID: ", dwarven[i].ID.ToString()));
                         dwarven[i].PlayRestriction = EditorGUILayout.TextField("Play Restriction: ", dwarven[i].PlayRestriction);
                         dwarven[i].SubTypes = EditorGUILayout.TextField("Sub-Types: ", dwarven[i].SubTypes);
                         dwarven[i].Cost = int.Parse(EditorGUILayout.TextField("Cost: ", dwarven[i].Cost.ToString()));
 
                         EditorGUI.indentLevel -= 1;
                         EditorGUILayout.Space();
                     }
 
                     if (GUILayout.Button("Add New Card"))
                     {
                         Dwarven newDwarven = CreateInstance<Dwarven>();
                         newDwarven.name = "";
                         newDwarven.Rarity = "";
                         newDwarven.ID = 0;
                         newDwarven.PlayRestriction = "";
                         newDwarven.SubTypes = "";
                         newDwarven.Cost = 0;
                         cm.cardList.Add(newDwarven);
                     }
                     EditorGUI.indentLevel = 0;
                 }
             }
         }
     }