User blog comment:Narfcwing/What is the chance of the gun being dropped in the minecraft Easter egg?/@comment-5686539-20130312171401

The actual drop rate for both the Blockhead and the Longbow is currently unknown. However, like most other Unique and Legendary items the drop rate is around 3.5 - 5%; give or take. The Blockhead can drop from any of the Creepers and the Longbow can only drop from the Badass Creeper. Also, you are overthinking this "how many times can I do the easter egg" thing. Farming the Creepers is not all that hard. Once you run through Caustic Caverns and the Creepers don't drop what you want, simply save and quit the game. Upon a reload, you will still be in the Caustic Caverns and can simply run to the easter egg area and do it all again. I personally have farmed three Longbows and one Blockhead. Just keep farming the Creepers and eventually they will drop one of those guns (or if you're lucky, both).