Minecraft mod for v1.8, using Minecraft Forge, based on The Yellow Submarine movie.  

Travel to PepperLand and fight the Blue Meanies!

In creative mode, all of the mod items and blocks can be found on the dedicated Yellow Submarine tab:

To get the submarine in survival mode, you'll need to hunt around and find each of The Beatles and Old Fred (who has come to request "HELP! HELP!" from The Beatles).  If you right click on each one, they will give you a piece of the submarine and a musical instrument.

You can use the pieces of the submarine to craft the Yellow Submarine Spawner:

This will then allow you to spawn in The Yellow Submarine:

Go inside, up the ladder to the bridge and pull the lever:

After a few seconds, the submarine will be transported to the PepperLand dimension.  Watch out for the mobs when you get outside - there are Blue Meanies, Apple Bonkers, Snapping Turks and The Glove!

Use one of the musical instruments to play some music - this will restore colour to PepperLand and damage nearby mobs.

The apples dropped by Apple Bonkers can be used to attack or "bonk" mobs, as well as conventional weapons.

As of v1.0.1, all PepperLand mobs drop Blueness:

This can be used to craft various things, such as tools "of Blueness" and Blue Meanie armour, using the standard shaped recipes:

Blue Meanies will sometimes drop armor items, and bosses will also drop a Mixing Desk (which presumably they have been secreting away to prevent music being played):

This can be combined with Band Stand Bricks to craft the Band Stand Spawner.  Smelt Blueness into "Ash of Blueness", and craft that with water to make the bricks:

These are then used along with the mixing desk and oak fences to craft the spawner:

As the name suggests, this spawns a Band Stand (!), complete with The Beatles, all ready to play:

The Band Stand includes a chest containing Sheet Music:

Right clicking on the floor of the band stand or the mixing desk with one of these items will make The Beatles play the requested song :-D  As they play, the surrounding area will regain its colour and nearby mobs will be damaged.

There are a few videos featuring the mod on YouTube here:

• https://www.youtube.com/playlist?list=PLxuoYINZ_UH7bHvk81A2uCNkjC0tNNwRr

P.S. You may want to use one of my Beatles skins, available here :-)

* In case it wasn't obvious, this mod is just for fun, not for profit and is not endorsed by or affiliated with The Beatles or Apple Corps in any way.