Air Elementals are enemies first appearing in Legend of Grimrock 2. They, along with Wyverns, spawn twice in the Forgotten River: once upon crossing the Cemetery's gate after solving its puzzle, another upon accessing the Sewers from the Archives.
Despite not being particularly powerful, fighting them can pose a challenge due to their ethereal form, which makes them immune to physical weapons. Magic is equally ineffective: they are immune to all schools except Air (which heals them). Additionally, their attacks will knock the party back a tile (provided there is open space behind them).
There are only two ways to damage them: using the Ethereal Blade (found in the Cemetery) and casting Dispel (its scroll can be found in a secret area of the Archives.