-Underwater Ruins: Aquatic Embryo
The Aquatic Embryo summons a baby dolphin pet to follow you around. Similar to Terraria’s pets, it’s invincible and you can only have one of them following you at a time.
-Igloo: Curing Kit
Curing Kits can be used to cure Zombie Villagers. Just interact with one, and it’ll start curing it without the use of golden apples and strength potions. You’ll find 2-4 of them at a time.
-Dungeon: Dark Amulet
Using the Dark Amulet will use up some of your HP in exchange for summoning a baby zombie minion. It is immune to the sun, and will protect you from other monsters until it dies.
-Desert Temple: Dusty Lamp
Similar to the Aquatic Embryo, the Dusty Lamp can be used to summon a small genie pet that will follow you around. Like the Baby Dolphin, you can only have one of them following you at a time.
-Village: Encrusted Hammer
Found in weaponsmith and toolsmith houses in villages, the Encrusted Hammer functions like a sword. It has about the same damage and durability as an iron sword, and can be repaired with emeralds. Attacking mobs with it has a small chance to make them drop emeralds.
-Woodland Mansion: Fang Gauntlets
The Fang Gauntlets deal 3 damage, and along with punching, you can right-click (or whatever your devices equivalent of right-clicking is) to use up some durability and summon a circle of fangs around yourself.
-Nether Fortress: Fortress Armor
Each piece of armor has the same durability and protection as iron armor. Wearing the full set will provide you with infinite fire protection.
-Piglin Bastion: Gilded Arrow
Holding the Gilded Arrow summons a ghast-like creature that will hover behind you. Right clicking with the arrow will make the creature fire a fireball.
-Ruined Portal: Glowstone Totem
Using the totem will trap all nearby monsters in a big block of fragile glowstone that will shatter after ten seconds. The totem can be used three times before it breaks.
-Abandoned Mineshaft: Heavy Boots
The heavy boots provides the same amount of protection as iron boots, and taking fall damage while wearing them will create a shockwave that damages mobs and cracks stone.
-Pillager Outpost: Illager Warhorn
Blowing the horn will give you the Bad Omen effect for a few seconds. Use it in a village to summon a raid. It can be used 3 times.
-Jungle Temple: Jawsprout
The jawsprout can be planted in soil like other crops, and can be grown with bonemeal. When fully grown, it will turn into a dangerous plant that will attack monsters for you.
-Stronghold: Scaly Saddle
Using the scaly saddle will summon a giant silverfish mount for you to ride. Jumping off of the mount will despawn it. It cannot be used in water.
-Buried Treasure: Ship in a Bottle
Similar to the scaly saddle, using the ship in a bottle will summon a squidboat mount for you to ride. Jumping off the mount will despawn it. It can be ridden on land, just very slowly. By putting it in a crafting table with four glowing ink sacs, you can make a Luminous Ship In A Bottle which will summon a Glowing Squidboat mount.
-End City: Shulker Shellguard
Crouching while standing completely still will summon a shield around you, at the cost of your vision. While shielded, you will be invincible. The armor can be dyed in a crafting table.
-Shipwreck: Tentacutlass
The tentacutlass deals the same damage as an iron sword, with a bit less durability. Attacking a mob with the sword will give you a few seconds of durability.
-Ancient City: Sculk Statue
By gathering blocks of sculk in the deep dark and feeding it to the statue, it will eat it in exchange for spitting out some xp for you.
You can use the command “/function usl_items” to give yourself every item that the addon adds, with descriptions of what they do. I plan on adding more items as more structures are added to the game.