Pnk Beanstalk Keys
All of the loot boxes associated with a normal Beanstalk are locked with some kind of key. These boxes include the ones you find around the trunk of the beanstalk, those you obtain from using Golden Eggs, and those you find in the base, heart, and crown of the beanstalk. In general, regular chests are seldom locked but might be trapped to trigger a response when opened.
Some keys you must find, others you have to create yourself by renaming items with an anvil. You can rename any item with a key value; the examples below use blaze rods. Note however, you probably want to avoid using placeable items like torches, or consumable items like food or arrows, or easily lost or mixed-up items like sticks.
Finally, BEFORE you even touch or try to open any beanstalk loot box or chest (even if it's locked), make sure you have as much luck effect as possible. The amount and quality of beanstalk loot is significantly affected by the player's luck status!
FFFF is the shortened form of the generic passphrase "Fee-Fi-Fo-Fum" which is the key for the only guaranteed-to-be-there loot box at the base of every normal beanstalk-- the bright lime-green box nestled somewhere in the midst of all that noxious stalkstone as shown in the pictures below.
TIP: Before looting a beanstalk, use an anvil to change the display name of some item to "Fee-Fi-Fo-Fum" so you can use that item to open this box. Raiding this loot box early is important as it contains several items that will help you overcome some of the other obstacles you'll face when looting the rest of the beanstalk (it might also contain some pretty nice loot-loot as well).
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This is the special Stained Bone key you'll find inside the beanstalk base's loot box-- the one unlocked by your FFFF key. This key's value is unique and linked to a particular beanstalk. You need this key to unlock all of the inner loot boxes generated with the beanstalk. Be careful not to lose this key (it always comes with a Curse of Vanishing) as you will need it to obtain a few other mod items besides beanstalk loot.
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TIP: Do not carry this key in your inventory as you raid the beanstalk. If you die, you will lose the key due to the vanishing curse on it. Secure the key somewhere safe, like in an ender chest or just leave it in the base, then retrieve it after all the fighting is done!
Use these keys to unlock the loot boxes you sometimes find on the outside bark of a beanstalk. These boxes are usually nestled near a bark knot but can be buried inside leaf blobs where the branch connects to the beanstalk's trunk. These boxes belong to the beanstalk's protector and worker zombies who are always named: "Fee", "Fi", "Fo", or "Fum" so each box is locked with one of these four names.
A worker zombie's stashed loot.
TIP: Use an anvil to rename four items, each with one of the names. Then use the matching named item to unlock a particular box like so: Try to open the box with your empty hand. The box will let you know who the box belonged to by showing a message like "Fo's Stuff! is locked". Now you know which named item to use to open the box; use the "Fo" key.
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After you've emptied all the items from a beanstalk's loot box, you might want to remove the locking key so you can reuse the box for your own storage. To do that you can use Bleaching Crystals. This recipe will remove the lock, custom name, and custom color. Note that the loot box MUST be empty for this recipe to work.
If you have the SmartHoppers mod installed, you can also recycle the loot box using that mod's "Recycle It!" item. Unlike the bleaching recipe, this recipe will unconditionally throw away the input loot box and give you an empty default shulkerbox.
Recycling a loot box (SmH required)