Hi-Ether

The Hi-Ether (ハイエーテル), also known as Dry Ether (エーテルドライ) or Ether2, is an item in the Final Fantasy series that restores MP. It is stronger than a regular Ether.

Final Fantasy
The Dry Ether appears in the Dawn of Souls, 20th Anniversary and iOS versions of the original Final Fantasy. The first one available is a rare drop by the Lich (Final Fantasy). Others must be found in the Bonus Dungeons.

Final Fantasy IV: The After Years
Dry Ethers restore 150 MP to one target. They can be won from the Tiny Mage enemy, as well as various other enemies, mainly the Mage-type monsters. They can also be bought for 50,000 gil in the final chapter in the Depths or Lunar Whale.

Final Fantasy V
Although not usable by normal means, Dry Ether is a Mix result by mixing a Hi-Potion with a Turtle Shell. This triples the Ethers' effect.

Before Crisis -Final Fantasy VII-
Hi-Ethers restore 200 MP. They can be bought for 500 Rank Points.

Final Fantasy XI
Hi-Ethers, originally titled Ether2, are obtained a variety of different ways, such as crafted with the appropriate skill in Alchemy, purchase from an NPC vendor, or as rewards for special events like Assault or Burning Circle fights. There are four different varieties of Hi-Ethers: Hi-Ether, Hi-Ether +1, Hi-Ether +2, and Hi-Ether +3.

The plus amount signifies a higher quality, with +3 being the best version, though other Ethers exist that restore more MP. There also exists a backpack called a "Hi-Ether Tank" that dispenses a Hi-Ether on demand (up to 20 times per tank), found sometimes from Assault.

Final Fantasy XII
The amount of MP Hi-Ether restores depends on the accessed Ether Lores, but after all Lores have been bought a Hi-Ether heals 250 MP. The Hi-Ether is not purchasable from shops, rather, it can only be acquired via treasure chests or synthesizing loot from the Bazaar.

The ingredients of Hi-Ethers are: Foul Liquid x2, Slime Oil x1, Unpurified Ether x2. It is known as "Flask of Viscous Liquid" in the Bazaar and costs 12,000 gil. The pack can be created repeatedly, however, due to a bug in game coding, Slime Oil is actually an extremely rare item; it was intended to be dropped by the flan genus of monsters, but because none of the regular flans actually do so, Slime Oil can only be obtained from the Orthros and the footracing minigame.

Hi-Ethers can be farmed at the Feddik River area of the Cerobi Steppe. All of the ten chests in the area spawn 50% of the time, with 50% chance of containing items, and, 50% to give a Hi-Ether if the treasure is items, without equipping the Diamond Armlet.

Final Fantasy Tactics
Hi-Ether can be used as an ability for the Chemist Job class, requiring 400 JP to master. Hi-Ethers restore 50 MP to a unit and costs 600 Gil to buy. Hi-Ether can be found with the Treasure Hunter ability at the Eagrose Castle, Fort Besselat South Wall, Limberry Castle Undercroft and Mullonde Cathedral.

Final Fantasy: The 4 Heroes of Light
Hi-Ethers can be bought for 10,000 G in the bonus dungeons, and also found in the Hunting Caves, Horne, and the Star Chamber. It restores 5 AP.