The wind howls. Then it tears your arms off.

Balls

DM threw this at our Level 3 party of 6.

Thankfully the cleric and my artificer have Faerie Fire and we were fighting it in a 20 ft cubic room.

It spent the entire fight bullying the cleric and they got knocked like 4 times, but we also 4 of us have healing capabilities so it was all good. Very fun boss fight overall.

Shouldn't it do slashing damage? The art depicts it slashing its target. Just my opinion

ncrnf,

sce

Quote from BirdMonk >>

Could I say...

Me: "Hey Mr. Invisible Stalker, I wanna know where the evil king is."

Stalker: "He is hiding in his top secret base that nobody knows about at coordinates x, y, and z..."

Me: "Alrighty let's go"

 Genius

It doesn't have the same movement ability as a regular Air Elemental; that is, the ability to move through a space as small as one inch without squeezing. That would seem very important to a being that is meant to be an invisible assassin.

What does it mean to "given quarry"
Do you need a piece, picture or some other link to be given to the stalkers so it can identify the location of the target?
Or it's completely free, so if you are a wizard who got a bad case of runs from a bad seafood meal at a local market, could you summon this elemental, tell it to "hunt down the fisherman who sold that crap to the guy from whom I bought the food that made my tummy hurt" and the damn thing would know what you are talking about AND know the exact location of this guy (if it's a guy) ?
Or it's that it doesn't know, but will find it eventually?

Just watched Vox Machina fight a couple of these!!!

its wa really good for my team they were ceeepted out

Quote from Chillagris >>

Shouldn't it do slashing damage? The art depicts it slashing its target. Just my opinion

 I think it looks like piercing damage. Also just my opinion

Two spells for that, I believe:

Magic Circle

Planar binding

Quote from healingpotion101 >>

Quote from Chillagris >>

Shouldn't it do slashing damage? The art depicts it slashing its target. Just my opinion

 I think it looks like piercing damage. Also just my opinion

 I don't think those are meant to represent literal blades, just tendrils of wind.

OK, SKT spoiler...

Faultless Tracker. The stalker is given a quarry by its summoner. The stalker knows the direction and distance to its quarry as long as the two of them are on the same plane of existence. The stalker also knows the location of its summoner.

The summoner in our party tasked an Invisible Stalker to recover a ring on or about a particular person where the ring has the following quality: "Neither the ring nor its wearer can be targeted by any divination magic or perceived through magical scrying sensors."

There is no mention that the Invisible Stalker uses any Divination Magic or uses magical scrying. The DM gave it a chance to successfully recover the ring...which it DID!

Could an Invisible Stalker (which is basically made up of air), catch fire from something like Searing Smite for the purposes of A) making it visible to other characters to attack, B) taking additional damage each round it fails the CON save?

Precisely how does "Immunity: Unconscious" work?

When dropped to zero HP, does it just instantly die (or revert to the elemental plane of air)?

Quote from EmeraldBeacon76 >>

Precisely how does "Immunity: Unconscious" work?

When dropped to zero HP, does it just instantly die (or revert to the elemental plane of air)?

 By default, most monsters just die when reduced to 0 HP.    However, usually players have the option of making the final blow nonlethal, knocking out the enemy rather than killing.  See PHB p. 198.  As an elemental, when reduced to 0 HP, just as you suggest it just goes back whence it came.   It doesn't hang around, unconscious (for entrapment in a magic circle, for instance).  Immunity to condition (unconscious) also means it cannot be affected by a sleep spell or the version of Imprisonment that puts a creature into a magical slumber, for instance.

Quote from Sarkis_89 >>

Got me thinking: what about hitting it with arrows? Would the arrows stuck, giving away its position, or would they just pass through it?

 My party's rogue did exactly this; I described it as:

Well, you've never seen an arrow do that before: It entered the space, swirled around wildly for a second, then fell to the floor, trailing a thin stream of vapor. Whatever this thing is, you hurt it.

I had to fight one of them after pulling out a dragon sword one of the creepiest creatures in dnd you can't see it fear of the unknown.