Torrent Taiaha

Description: The Torrent Taiaha looks like a kind of viscious oar made of green stone with a paddle at one end and holes bored through the shaft so that you can see through it in various places. On the stone various maritime creatures with tentacles, gills, and teeth can be seen having been carved and painted into it with a particularly notable black salamander like creature with tentacles growing on it's back on the paddle end of the Taiaha.
The Oar is remarkably lightweight and a sloshing sound can be heard from within whenever it's swung, shaken, or quickly moved. Upon holding it for a little while a stream of green-ish water starts creeping from the interior and will calmly snake around the object and the wielders hand. This water possesses a rudimentary intelligence and can be identified as a minor elemental, it retreats when forcefully interacted with and entreated to snake around the wielders hands but it doesn't recognise any further interactions.

Stats: The Torrent Taiaha can be wielded as a +1 Magic Quarterstaff.
When making Melee Attacks with the Torrent Taiaha you can choose to attack using the water inside instead. When you do so the attack has a range of 10ft, it uses your proficiency with Quarterstaffs and your Wisdom Modifier for its attack and damage rolls, and deals 1d4 Cold damage on hit. After this attack the water retreats back into the staff.
Also whilst holding the Taiaha you can stand on and move across any liquid surface as if it was solid ground. If you end your turn on a liquid in this way, you sink into it as normal until you stand on solid ground again.
In addition while holding the Taiaha you can cast the Flood or Part Water effects of the "Control Water" spell without expending a spell slot. The spell ends early if you are no longer holding the Taiaha. Once the Taiaha has been used to cast this spell it can't do so again until the next dawn.
(Link to Control Water Spell for reference: https://www.dndbeyond.com/spells/control-water )

Mechanics & Inner Workings

The inner workings of the Taiaha is a mystery as the item is not constructed according to any known methods of Magic item manufacturing.
A quick study of the item reveals that the item doesn't so much "do" anything as much as it acts as a conduit to some form of elemental power.

Manufacturing process

We have no clue.

History

Found alongside the suspended Shark-like Triton figure held within the bubble at the base of the Sodden Palm, it was likely theirs before it fell into the party's hands.

Significance

This was likely an artifact of the Triton held within the bubble at the base of the Sodden Palm, meaning it is a true artifact of another plane of existence, of Gishil.

Item type

Weapon, Melee

Creation Date

???

Rarity

Rare- This in design, material, and enchantment is not the work of anyone on this plane and as such can be considered extremely valuable, the fact that the enchantment is a potent one is just icing on the cake.

Weight

1kg

Dimensions

5'2" long x 2" wide (Not counting paddle)

Base Price

900GP

Raw materials & Components

The Taiaha is constructed of a lightweight green stone, darker than jade but lighter than shale, that isn't recognisable and is likely alien to this Plane considering it's origins. The only other "material" that is present within the item is the water which lives inside of it which upon observation just looks like regular water.

Tools

To create the actual body of the item you wouldn't need much in the way of tools, just basic stoneshaping apparatus. To create the enchantment however, what that requires is currently unknown.