diff --git a/app/gilded-rose.ts b/app/gilded-rose.ts
index ee55134..283531d 100644
--- a/app/gilded-rose.ts
+++ b/app/gilded-rose.ts
@@ -19,47 +19,51 @@ export class GildedRose {
 
     updateQuality() {
         for (let i = 0; i < this.items.length; i++) {
-            if (this.items[i].name != 'Aged Brie' && this.items[i].name != 'Backstage passes to a TAFKAL80ETC concert') {
-                if (this.items[i].quality > 0) {
-                    if (this.items[i].name != 'Sulfuras, Hand of Ragnaros') {
-                        this.items[i].quality = this.items[i].quality - 1
+            if (this.items[i].name == 'Aged Brie') {
+                if (this.items[i].quality < 50)
+                    this.items[i].quality = this.items[i].quality + 1
+            } else if (this.items[i].name == 'Backstage passes to a TAFKAL80ETC concert') {
+                if (this.items[i].quality < 50)
+                    this.items[i].quality = this.items[i].quality + 1
+                if (this.items[i].sellIn < 11) {
+                    if (this.items[i].quality < 50) {
+                        this.items[i].quality = this.items[i].quality + 1
+                    }
+                }
+                if (this.items[i].sellIn < 6) {
+                    if (this.items[i].quality < 50) {
+                        this.items[i].quality = this.items[i].quality + 1
                     }
                 }
             } else {
-                if (this.items[i].quality < 50) {
-                    this.items[i].quality = this.items[i].quality + 1
-                    if (this.items[i].name == 'Backstage passes to a TAFKAL80ETC concert') {
-                        if (this.items[i].sellIn < 11) {
-                            if (this.items[i].quality < 50) {
-                                this.items[i].quality = this.items[i].quality + 1
-                            }
-                        }
-                        if (this.items[i].sellIn < 6) {
-                            if (this.items[i].quality < 50) {
-                                this.items[i].quality = this.items[i].quality + 1
-                            }
-                        }
+                if (this.items[i].quality > 0) {
+                    if (this.items[i].name != 'Sulfuras, Hand of Ragnaros') {
+                        this.items[i].quality = this.items[i].quality - 1
+                        if (this.items[i].name == 'Conjured Mana Cake' && this.items[i].quality > 0)
+                            this.items[i].quality = this.items[i].quality - 1
                     }
                 }
             }
+
             if (this.items[i].name != 'Sulfuras, Hand of Ragnaros') {
                 this.items[i].sellIn = this.items[i].sellIn - 1;
             }
+            
             if (this.items[i].sellIn < 0) {
-                if (this.items[i].name != 'Aged Brie') {
-                    if (this.items[i].name != 'Backstage passes to a TAFKAL80ETC concert') {
-                        if (this.items[i].quality > 0) {
-                            if (this.items[i].name != 'Sulfuras, Hand of Ragnaros') {
-                                this.items[i].quality = this.items[i].quality - 1
-                            }
-                        }
-                    } else {
-                        this.items[i].quality = this.items[i].quality - this.items[i].quality
-                    }
-                } else {
+                if (this.items[i].name == 'Aged Brie') {
                     if (this.items[i].quality < 50) {
                         this.items[i].quality = this.items[i].quality + 1
                     }
+                } else if (this.items[i].name == 'Backstage passes to a TAFKAL80ETC concert')
+                    this.items[i].quality = 0
+                else {
+                    if (this.items[i].quality > 0) {
+                        if (this.items[i].name != 'Sulfuras, Hand of Ragnaros') {
+                            this.items[i].quality = this.items[i].quality - 1
+                            if(this.items[i].name == 'Conjured Mana Cake' && this.items[i].quality > 1)
+                                this.items[i].quality = this.items[i].quality - 1;
+                        }
+                    }
                 }
             }
         }
diff --git a/test/jest/gilded-rose.spec.ts b/test/jest/gilded-rose.spec.ts
index 613639f..387dae9 100644
--- a/test/jest/gilded-rose.spec.ts
+++ b/test/jest/gilded-rose.spec.ts
@@ -9,7 +9,7 @@ describe('Gilded Rose', () => {
         const items = gildedRose.updateQuality();
 
         // Assert
-        expect(items[0].name).toBe('bar');
+        expect(items[0].name).toBe('foo');
     });
 
     it('sword quality drops by 1', () => {
@@ -20,6 +20,86 @@ describe('Gilded Rose', () => {
       const items = gildedRose.updateQuality();
 
       // Assert
+      expect(items[0].quality).toBe(0);
+    });
+
+    it('quality degrades twice as fast after last sell in day', () => {
+      const gildedRose = new GildedRose([new Item('Item', 0, 5)]);
+
+      const items = gildedRose.updateQuality();
+      
+      expect(items[0].quality).toBe(3);
+    });
+
+    it('aged brie quality increases by 1', () => {
+      const gildedRose = new GildedRose([new Item('Aged Brie', 5, 10)]);
+
+      const items = gildedRose.updateQuality();
+
+      expect(items[0].quality).toBe(11);
+    });
+
+    it('aged brie quality does not increase over 50', () => {
+      const gildedRose = new GildedRose([new Item('Aged Brie', 5, 50)]);
+
+      const items = gildedRose.updateQuality();
+
+      expect(items[0].quality).toBe(50);
+    });
+
+    it('backstage passes quality increse by 2 when 10 days or less', () => {
+      const gildedRose = new GildedRose([new Item('Backstage passes to a TAFKAL80ETC concert', 6, 5)]);
+
+      const items = gildedRose.updateQuality();
+      
+      expect(items[0].quality).toBe(7);
+    });
+
+    it('backstage passes quality increse by 3 when 5 days or less', () => {
+      const gildedRose = new GildedRose([new Item('Backstage passes to a TAFKAL80ETC concert', 2, 5)]);
+
+      const items = gildedRose.updateQuality();
+      
+      expect(items[0].quality).toBe(8);
+    });
+
+    it('backstage passes quality drop to 0 after final day', () => {
+      const gildedRose = new GildedRose([new Item('Backstage passes to a TAFKAL80ETC concert', -1, 5)]);
+
+      const items = gildedRose.updateQuality();
+      
+      expect(items[0].quality).toBe(0);
+    });
+
+    it('sulfuras quality remains the same', () => {
+      const gildedRose = new GildedRose([new Item('Sulfuras, Hand of Ragnaros', -1, 80)]);
+
+      const items = gildedRose.updateQuality(); 
+      
+      expect(items[0].quality).toBe(80);
+    });
+
+    it('sulfuras sell in days remain the same', () => {
+      const gildedRose = new GildedRose([new Item('Sulfuras, Hand of Ragnaros', 2, 80)]);
+
+      const items = gildedRose.updateQuality(); 
+      
+      expect(items[0].sellIn).toBe(2);
+    });
+
+    it('conjured item quality drops twice as fast', () => {
+      const gildedRose = new GildedRose([new Item('Conjured Mana Cake', 4, 5)]);
+
+      const items = gildedRose.updateQuality();
+      
+      expect(items[0].quality).toBe(3);
+    });
+
+    it('conjured item quality drops twice as fast when sell in days are over', () => {
+      const gildedRose = new GildedRose([new Item('Conjured Mana Cake', 0, 5)]);
+
+      const items = gildedRose.updateQuality();
+      
       expect(items[0].quality).toBe(1);
-    })
+    });
 });