As of Minecraft 1.7.3, naming a Sheep "jeb_" with a nametag will cause its wool to start changing colors.

The Steve skin comes from an unfinished spiritual successor to Left 4K Dead, another game by Notch.

There are quite a few base potions in the game's code that were left with no method to craft them in 1.9 beta pre-release 3. These potions include: Clear, Diffuse, Artless, Thin, Bungling, Suave, Smooth, Debonair, Charming, Refined, Cordial, Sparkling, Potent, Rank, Acrid, Gross, and Stinky.

While they can still be obtained using commands, they have no effect, and take the appearance of a water bottle.

The End Stone texture is simply an inverted cobblestone texture.

During the development of Beta 1.7, Mojang was considering adding spike blocks that would function like a piston, except with spikes instead of a flat piston head. They instead decided to add sticky pistons that could pull blocks, and make spike blocks into a static block that could simply be pushed and pulled with the sticky pistons instead. Sticky pistons were implemented, but they couldn't decide how they wanted spike blocks to look or function.

It's possible to place a bed in The End. However, as the developers didn't want the player to sleep in The End, beds will explode when placed. It's possible to actually defeat the Enderdragon with precise placing of beds. Upon exploding, they will injure the Enderdragon with very high damage if it is close by.

The age of a tree is determined by the number of rings on its stump. With that logic in mind, every tree in Minecraft is two years old.

If a Spider is spawned in the Nether, there is a very rare chance that it will spawn with a Wither Skeleton riding it. This behavior normally goes unused, because Spiders don't spawn in the Nether.

Baby zombies can occasionally be found riding chickens.

Some of the Ghast's sounds were recorded from composer and sound designer C418's pet cat.

There is an unused enemy in the game called Giant. This mob is a huge Zombie with considerable health and deals heavy damage. They can only be hurt by being hit in the legs. Giants were added in the last version of Survival Test, but haven't been used since. They can still be spawned through hacks, however. Additionally, they can be spawned using the command "/summon Giant" in version 1.7 of the game.

The collective noun for a group of Endermen is a "haunting" of Endermen.

There is a 1 in 2500 chance that a rabbit will spawn hostile, and attack players who come within four blocks. This rabbit is referred to as "The Killer Rabbit of Caerbannog" in the player death screen. This is an Easter egg based off of the Rabbit of Caerbannog from the British comedy film, Monty Python and the Holy Grail. In Peaceful difficulty, the killer rabbit will not despawn and will still try to attack players, but will do no damage.

When the .ogg file of the Disc 11 is run through a spectrogram, it is possible to see an image of what appears to be Steve's head and some numbers. Many fans have speculated why these are here but no official answer has ever been given.

The Enderdragon can be damaged with snowballs.

One of the possible splash screen lines will read "Follow the train, CJ!" This is a reference to the Grand Theft Auto: San Andreas mission "Wrong Side of the Tracks", in which the line is exclaimed by Big Smoke upon the mission's failure.

Whenever the player unlocks an achievement in the PC release, the notification will read "Achievement get!" This is a reference to the Japanese release of Super Mario Sunshine, where upon collecting a "shine" the words "Shine Get!" pop up on screen.

If the game's language is set to Australian English, there are a number of interesting changes that occur, including all new names for each type of tree, pigs being renamed wombats, and many more. Many in-game messages are also changed, like if you try to use a bed when a hostile mob is nearby, it will say "You can't sleep. The neighbors are having a party." instead of "You can't sleep. There are monsters nearby."

If the game crashes, a witty comment is placed at the very beginning of the crash report. These comments include parodies of Zero Wing's "Somebody set up us the bomb", lines from "2001: A Space Odyssey", and even Minecraft in-jokes like "You should try our sister game, Minceraft!"

In the texture for the Armor Stand, in an unused area in the bottom right, the word "SEARGE" can be seen in a black box. This is here because Searge was the creator of the armor stand.