Have you ever wanted a balloon in Minecraft? Well now you can! :D
What you need:
1. An animal of your choice
2. A lead
3. A fence (optional, it's just for display)
4. Minecraft version 1.9
Step 1: Get Your Animal
Just as the title says, get and animal of your choice!
I used a pig as an example.
You can either use a spawn egg, or use /summon Pig
Step 2: The Rope!
Next you need a lead.
Attach it to the animal, by right clicking it while holding the lead.
Step 3: Let It Fly!
After that you need to type this command, /effect @e[type=Pig] minecraft:levitation 500000 1
Make sure you're holding the lead before doing that command! :D
Step 4: Have Fun
Also if you're tired of holding a lead, you can place a fence and right click it with the lead, and your balloon is anchored to the fence! :D
Again, it only works for Minecraft 1.9