Here's a cool DIY idea for a cat enrichment toy. Glue together a group of toilet paper rolls inside a tissue box and randomly fill the tubes with treats. Your cat will be stimulated when they "hunt" for a treat. So simple and inexpensive.
The Climbing Pole: "This is a tall climbing post fashioned from a wrapped in cotton clothesline rope. It stands away from the wall with spacers so the cats can get their paws around the post for better climbing.