Treasure
Various kinds of treasure. Ruby/sapphire are primarily dropped by their ores but you can also find small gems and sometimes large gems from pots, chests, etc.
Rope Pile
Obtainable from crates. Max stack of eight and gives eight ropes when consumed. Ropes can be used to throw and launch rope, which are climbable semi-solid blocks affected by gravity.
Bombs and Bomb Bags
Bombs are obtained from crates. Throwable item, explodes when it hits a block/player/entity. Also has sticky/bouncy variants, craftable using bombs with respectively Bomb Paste/Slime Balls.
Bomb Bags are obtained from crates or made via compacting three bombs. Primarily acts as a storage/source of bombs as they can both be right-click used to give three bombs or putting three bombs in a crafting grid will produce a Bomb Bag to compact them.
Bomb Paste
Dropped from crates, rarely spiders or more commonly cave/mineshaft spiders. Can be used with bombs to craft sticky bombs and each bomb paste can be used 64 times before being depleted completely.
Parachute
Non-usable item that auto-activates if you fall +3 blocks. It will be consumed on use and automatically set your fall-height to 0 before landing, preventing any fall damage on activation.
Mattock
Obtained from crates. Has durability halfway between stone/iron and twice the mining speed of gold pickaxes. When they break, they drop an reusable throwing item called Mattock Heads. They can also be used as a weapon.
Gem Tools
Craftable from sapphire, ruby or emerald. Not shown but you can also craft hoes. Emerald, sapphire and ruby respectively have the harvesting-level of stone, iron and diamond however their speed and durability is generally equivalent to being better than their vanilla equivalents.
Pitcher's Mitt
Off-hand slot gloves that adjust the aim of projectiles like rocks and skulls to be straight.
Climbing Gloves
Gloves that allow you to climb. When equipped in off-hand, stand against a +2 block high surface and hold right-click to climb.
Spring Shoes
Equipable boots-slot item that provides a Jump Boost effect when equipped.
Spectacles
Rare special glasses that give you permanent Night Vision when equipped.
Cape
Equipable chest-slot item that completely negates fall damage when equipped. Basically a permanent equipable version of the Parachute item.
Jetpack
Jetpack's are awesome! Right? When equipped in chest, jumping will make you levitate semi-quickly, allowing you to hover at a quickly ascending pace or reach places out of reach for you.
Whip
A standard weapon. Medium-high durability, easily craftable (two leather and a stick) and does 2.5 hearts of damage each strike.
Machete
Melee weapon. Does five hearts of damage and can cut through webs with ease.
Pistol
A much weaker version of the Shotgun. Does decent damage and ammo is much easier to craft, cost wise.
Shotgun
Rare and very powerful gun. Ammo is somewhat costly but each shot does 10 hearts of damage at max.
Webgun
A gun that fires cobwebs. Spawns climbable cobwebs on hit and entity-hit stuns enemies.
Freeze Ray
A gun that fires blasts of ice. Projectiles spawn ice and stun enemies for a period.