Deep Desire

[Newton Philis]

What appeared to be the object of your desire, suddenly comes to life as it lashes out at you with its tentacles.

Deep Desire CR 5
XP 1,600
N Medium aberration (shapechanger)
Init +5; Senses all-round vision, darkvision 60 ft.; Perception +11

----- Defense -----
AC 16, touch 11, flat-footed 15 (+1 Dex, +5 natural)
hp 52 (7d8+21)
Fort +5, Ref +5, Will +6
Defensive Abilities amorphous, chameleon; Immune critical hits, precision damage

----- Offense -----
Speed 5 ft., Climb 5 ft.
Melee slam +10 (1d8+6 plus grab)
Special Attacks constrict (slam, 1d8+6)

----- Statistics -----
Str 19, Dex 12, Con 17, Int 10, Wis 12, Cha 10
Base Atk +5; CMB +9 (+13 grapple); CMD 20 (can’t be tripped)
Feats Improved Initiative, Lightning Reflexes, Skill Focus (Stealth), Weapon Focus (slam)
Skills Climb +14, Disguise +10 (+30 if using mimic desire), Perception +11, Stealth +14; Racial Modifiers +20 Disguise (if using mimic desire)
Languages Undercommon
SQ detect desires, mimic desire

----- Ecology -----
Environment any underground
Organization solitary, pair, or cluster (3-6)
Treasure standard

----- Special Abilities -----
Detect Desire (Sp) This creature constantly probes for surface thoughts, hoping to find a victim’s deepest desire. This is similar to a Detect Thoughts spell but with a range of 120 feet, and creatures who succeed on their DC 16 Will save, avoid having their desires detected. This is a Constitution-based, divination, mind-affecting ability.
Mimic Desire (Sp) After successfully detecting desire in a victim, this monster can assume the form of that desire. This can be an object or a creature of Medium size or smaller, such as gems, food or a desired mate. The Deep Desire cannot substantially alter its size, but can alter part of its body to look like the surrounding cavern floor or wall, with the remainder of its body looking like the adjacent smaller, desired object or creature. Using the thoughts from the victim, it can even mimic the form’s sounds, smells, and behaviours. The Deep Desire gains +20 racial bonus on Disguise checks to imitate this object or creature. Disguise is always a class skill for a Deep Desire.
Chameleon (Ex) The Deep Desire also uses its shapechanging ability to avoid powerful creatures or those with no mental desires (e.g., undead). It can take on the color and texture of nearby objects, including cavern floors and walls. It receives a +10 enhancement on Stealth while in this form.

This subterranean creature is an ambush hunter, using its prey’s deepest desire to lure it close enough to launch a surprise attack. Most of the time it assumes the form of edible mushrooms or morsels of food for the pale beetles that often scurry along Nar-Voth’s caverns. Occasionally it will encounter derro and mimic a patch of cytillesh/brain mold. Or it will shapechange into a vein of precious metals or gems for wandering duergar. Surface dwellers who have wandered this deep into the Nar-Voth often have more desperate desires; encountering a shapechanged ancient portal to the surface, or a kindly dwarven map maker. Those with more noble pursuits often find wounded maidens, or long-lost relatives.

Deep Desires are highly sought after by the drow. They often send patrols into the Nar-Voth with the sole purpose of capturing Deep Desires. Their abilities are prized by drow interrogators, who domesticate and train them. Finding out what your enemy desires the most, is an invaluable tool (especially other drow Houses). The cruel drow also enjoy the ironic humor of watching their captives getting devoured by their greatest desires.

[Mikko Kallio]

Congratulations on making the Top 16 in RPG Superstar! I'm Mikko Kallio, an RPG design blogger, freelancer, and former RPG Superstar finalist. Some of my freelance work involves designing monsters for Paizo's Adventure Path bestiaries. I'll review your monster much like I do when a fellow freelancer asks me to have a look at an assignment they're going to turn in.

Name and concept

I don't like the name; while it certainly describes the monster well, it's probably one of my pet peeves that a concrete, physical being has the name of an abstract concept.

The concept isn't very new; in fact, it's very old school. The mimic is one of the most classic D&D creatures, also one of the most hated/loved old school monsters, I think. The question is: is this monster different enough from mimics and other mimic-like creatures? I'm afraid I'm going to have to say no. Besides its shapechanging ability, it really has no other defining features, nothing unique that makes it more than an imitation of the mimic. Pun intended.

Descriptive line

The descriptive line isn't particularly interesting, and it also assumes a ”you” being surprised by the creature, which makes it less usable as read-aloud text.

Stat block

There's no ability called ”all-round vision”, it's ”all-around vision”. ”Climb” shouldn't be capitalized when it refers to a climb speed rather than the Climb skill. ”If using mimic desire” should be ”when using mimic desire”. You've used a hyphen instead of an en dash in ”3-6”. Other than that, the formatting looks correct.

It should have three even and three odd ability scores.

On average, its stats are a bit below the target values for its CR.

It's very, very slow, which means that if it isn't able to grab a creature with its first attack, it's already lost the fight.

Special abilities

The special abilities should be listed alphabetically. Also, the names of spells (or the creature's name) should not be capitalized. You've also used a British spelling (”behaviours”). Furthermore, ”Constitution-based” isn't something you can list along with ability/spell descriptors. It's always a separate sentence.

As for the abilities themselves, detect desire and mimic desire are rather vague as abilities. In fact, in one of my monster design advice articles, I used ”knowing a target's deepest desire” as an example of a mechanically vague ability. The problem is that the GM has to know the characters really well. In a long-running campaign, that's actually possible, and an encounter with a deepest desire might be really interesting. But in Pathfinder Society, for instance, the GM would have to ask the players or make a wild guess. Both of these options could potentially break the immersion.

Description

You've used a lot of words to give examples of what the deepest desire could look like when encountered. That's probably because you also realized the abilities are mechanically really vague.

I like the second paragraph about how drow use them. I suppose that could be an interesting idea for an encounter. More often than not, however, the deepest desire will be random encounter much like its better-known cousin, the mimic.

Oh, and avoid using the future tense ”will”.

Verdict

While the idea is intriguing as such, it's nothing new, and I think the execution also falls short. I don't recommend this entry for advancement.

[Owen K. C. Stephens]

NOTE TO VOTERS: There was a template error for some contestants that placed name, CR, and XP all on one line. That is not a contestant error, and they should not be penalized for sticking to the template we told them to use.

A note on capitalization.
Spells are not capitalized in running text. ("This is similar to a Detect Thoughts spell")
Monster names are not capitalized in running text. ("They often send patrols into the Nar-Voth with the sole purpose of capturing Deep Desires.")

The description is an odd case, but you went the route of having the least information. Look at how we handled this with the very-similar mimic - pick one form it might be (I'd have gone with some of your suggestions in it's full description -- food, water, gems), and write the read-aloud based on that assumption.

This is a telepathic mimic. That's an interesting idea, but it comes with problems as Mikko noted, and you don't address them. A neat idea only makes a great monster if you execute it in a way that is fun and interesting. having a GM constantly ask players what their deepest desires are not only slows the game, it gives away the secret. Once a player says his deepest desire is a tuna fish sandwich, he knows not to get near one he finds sitting on the floor in Nar-Voth.

I do not recommend this monster for advancement to the next round.

[Adam Daigle]

Congrats on making it to this round! May you have the luck and talent to push all the way through to the end!

My Judging Process:

I’m treating these like a pre-development pass.

When I develop a monster for the Adventure Path bestiaries (or anything really), one of the first phases is where I print out the monster entry, and look it over, marking up the page with notes and highlighting any problems that I need to address later when I really dig into it. Much of the time I’m circling things in the stat block or flavor text and leaving a quick note. Most often, this quick note-making pass is performed while I’m writing out art orders for the monsters so I can make sure that the description I give to the artist is what the final monster will be. This is where I make note of any changes I plan to make (some of which I’m sure frustrate some of my freelancers from time to time).

I figured the best way to judge this round is to treat it like my normal day-to-day work and do what I mentioned above. I’m going to judge this round in a similar manner to how I’d treat a monster I ordered from a freelancer if I asked one of my freelancers to just send me something within the same parameters that you’ve been given. Some of the things I comment on might seem nitpicky or overly critical of a small element, but I blame that on my job. I’ll probably even use terms that aren’t that familiar outside of publishing. :)

One thing to keep in mind is that nothing in my review here is personal, and since tone is difficult to communicate online sometimes, imagine my comments and critiques read in a friendly and nudging way. To heighten the experience, imagine all of these comments scribbled in purple ink on a sheet of paper containing your monster.

I start by googling the name to make sure that it isn’t something already existing, a weird term that could mean more than one thing, or isn’t secretly offensive or illegal.

Then I read the flavor line under the monster’s name.

Then I work my way down the statblock looking for anything that stands out or is in the wrong place or is formatted wrong. Most of these comments are just things that jumped out at me from a glance and are super easy to fix while I’m developing a monster. (I don’t get annoyed at my freelancers for these little typos and oversights unless it gets really sloppy or persistant.) During this I also look at how much the stats match up to Table 1–1 and how different elements of the design account for numbers that are off the average. During this part I often have questions about why a decision was made or why the creature has this element. I jot these down. Many times I figure out the decision once I read the flavor text and go back and scratch those notes out.

This leads me to the flavor text. This is the part of the monster where I get to see how well the designer can write. (One of the reasons I often test new contributors with monsters is that it pairs up design and writing in a nice compact package.) I also look at how the designer used the tight wordcount. This round’s rules used pretty much the same wordcount that we’d use for one of those monsters, and it can be difficult finding the right balance of flavor text and statblock. Too much flavor can sometimes result in a boring creature mechanically, but when 90% of the turnover is statblock, the GM doesn’t have much to go on for how to run the critter.

In judging, I also go back and evaluate some of my critiques and revise after looking at the monster again with fresher eyes.

I notice that I say “probably” a lot in my reviews. When I use that word I pretty much mean that I’d either really think it over and research a few things more than I normally would before making a particular change. This would certainly include me turning around in my chair and getting feedback from other developers (including any editors that heard me in the next cube over).

Even though most of my comments are very “stream of consciousness,” I spent a good amount of time with each of these monsters, typically an average of 30 minutes on each submission. Some more than others. I also did all of my reviews blind without seeing the other judge’s comments. I didn’t want what they had to say influence me. I apologize ahead of time if we end up being repetitive.

And now onto the monster!

• I recognize this is completely subjective, but the name turned me off. It seems punny, and before I’ve even read the monster I imagine it to be pulling the monster trope of “the alluring beast.” A trope that has really grown poorly on me over my years of making and researching monsters.

• Don’t include “you” in the intro descriptive text.

• You list amorphous in its defensive abilities line and then go on to include what that ability does for the Immune section. That’s superfluous and could have saved you five words.

• A monster’s stats should include three odd stats and three even ones.

• In the skills line, you don’t need to include the bonus on Disguise checks when using its special ability, and you certainly don’t need to include it as a racial modifier. That’s also superfluous and would have saved you another 13 words.

• You don’t need to capitalize the name of the monster anywhere except in the title. (Unless it is a single unique creature, which in that case it would be treated as a proper noun.)

• We almost always try to use the same language for the same things. At the end of the detect desire ability, you mashed three pieces of information together in a way we don’t do. You need to mention that the DC is Constitution-based. You need to state that this is a divination effect (which is already obvious because it uses many of the same parameters of detect thoughts, it’s probably not something you even need to mention). That last line should probably read “This is a mind-affecting effect, and the save DC is Constitution-based.” Also, you don’t need to capitalize detect thoughts.

• In the speed line, you don’t capitalize climb when it’s not talking about the skill. Also, this thing seems really slow without giving a reason why this is in the description. If something is really off a baseline assumption, you shuld make sure to highlight why that is. That kind of thing helps GMs when running the creature.

• It’s AC and saves are a bit low for a creature of this CR.

• The entry doesn’t need the word slam in the parenthesis after the constrict UMR, only the damage is needed there.

• It’s damage by itself is a bit low for a creature of this CR, but if you factor in its ability to make its grab, the contrict helps get it about where it should be.

• Okay, so I was wrong thinking that this was going to be an allure monster. It’s instead a non-sticky cave mimic. This makes me wonder what it looks like in its natural state. Does it mimic things pretty much all the time, or does it spend a lot of time in some sort of shapeless blob?

• List special abilities in alphabetical order. Pretty much always organize things in alphabetical order unless there is another precedent or some other strong reason that makes more sense than alphabetical order.

• In your flavor text, you keep referring to “the Nar-Voth.” It’s just Nar-Voth.
The drow connection is kind of interesting, but it doesn’t really scream Nar-Voth. I feel like you’re getting off focus with that element.

• Do your best to excise the use of “will” in your text.

• I appreciate your effort on this creature. It has a seed of something there, but it just doesn’t strike me as it’s presented. I don’t recommend this monster to advance.

[Lucus Palosaari]

Mimic, Nar-Voth Edition. I've seen this creature done, and done different ways. It's not a bad version of it, but it's basically just one more filler creature. I say Mimic in my first quick phrase, but there is likely a better creature to compare it to.

Your little addition about the drow almost detracts from this creature. I feel like you were basically trying to make a really good ambush predator, but I wouldn't even bother trying to employ it because only the dumbest and greenest of PCs would be fooled. I would REALLY need to sell it.

Also, this.

[Cthulhudrew]

This seems like a combination of a doppelganger and mimic, but without a really unique niche of its own to set it away from those two. The name doesn't wow me; this sounds like a name given to it by others, though I would expect an intelligent creature to have its own appellation.

Also, none of the judges mentioned it, so maybe I'm wrong, but shouldn't the creature's Detect Desire ability be listed as a spell-like ability in the Offense section?

There doesn't seem to be any hook that makes this a Nar-Voth creature (or even a Darklands creature) other than it just being described as being from there, and that's the biggest drawback to me as far as it meeting the challenge of this round.

[Maurice de Mare]

13th monster I have seen.

You are not lucky nr 13.

Your current rank is 12th.

[Tosscobble]

The monster is not new or super.
What is superstar is your writing and how you describe and fit it into nar voth.

Great job but bad monster. It needed something more than a back story to make it stand out and become its own new creature.

[Feros]

Congratulations on making the Top 16! :D

The descriptive line is problematic given the nature of the creature. What if the GM isn’t aware of the PC’s deepest desires? This monster is hard to use except when the PCs have a distinct goal. Then it could be useful.

Aside from that it is just a mimic that reads thoughts and has a greater range of shapechanging ability. That isn’t very interesting or all that new…doppelgangers have been doing that in the game forever. The tie to Golarion is good, but not exceptionally strong.

There really isn’t much else for me to say here. There is an interesting idea here, but other monsters exist that already fill those roles. As such I will not be voting for this entry.

[R D Ramsey]

Name- Deep Desire. Don't like punny names. Also a name prone to causing confusion.

Description- It has tentacles. Not a lot else to work with here.

Special Abilities- They make sense together, but there's nothing new here. It's just a mimic that can target its disguise a bit better.

Nar-Voth appropriate- Not especially. Some ties to the Drow that do sound Drow-ish, but nothing that makes the creature itself particularly Darklands-y.

Mojo- Little. As mentioned, there's really nothing new here. Maybe if each creature saw it differently and it could sow discord in a party as they argue over it?

Will players remember in 6 months- No. At best they'll remember a slightly odd mimic.

[quillblade]

Monster, I re-dub thee Doppelmimic. Okay, this is how I see an encounter with this monster going:

GM: As you're walking through the ancient tunnels of Nar-Voth, Player 1, give me a Will save.
Player1: Uhh... I get a 12.
GM: About a hundred feet away, you see... something. What is your character's deepest desire?
Player1: Right now? A bath.
GM: A bath? Seriously? Okay, fine, you see a hot, steaming bathtub, complete with soap and bubbles.
Player1: Oh, I'm not suspicious at all.

That may be an exaggeration ;) If a GM already knows the characters really well, he/she can use something more appropriate than my example, without having to ask the give-away question. (Incidentally, the phrase "roll your Will save" is the bane of illusion and enchantment-based creatures, but that's neither here nor there).

The low speed on this thing means that when the players figure out that there's something funny going on, it can't actually get away from them or chase after them. Not exactly the most satisfying of encounters for a GM, and might possibly become known as 'free XP'. (I've had similar issues with running mimics, which are faster.) It probably should have had a better land speed, because if it doesn't pull off that initial ambush it's toast.

If the drow send hunters out into the wilderness to find Deep Desires, does that mean that the Deep Desires appear to them in their natural form? Also, how does the Deep Desire determine what is a "powerful creature" in order to avoid it with its chameleon ability? To me, the creature's descriptive text isn't that helpful.

[Dana Huber]

quillblade wrote:

Incidentally, the phrase "roll your Will save" (or similar) is the bane of illusion and enchantment-based creatures everywhere.

Hence my habit of making sure I know my player's will saves in advance, and roll them ahead of time when I know that I have an encounter in that category planned. :)

/random two-cent intrusion, sorry

[RJGrady]

Rather than literally, and in an open-ended way, reflect something's "deepest desire," it ought to default to something desirable (food, shelter, companionship, mates, and psychological equivalents, such as treasure). Since "deepest desire" is fairly subjective, it seems like this creature ought to use a lot of intelligence or intuition or divination, but it doesn't. It's a mind reader of an oddly specific type.

I think you would have done better by simply combining the doppelganger's detect thoughts with a mimic's shapechanging, making "deepest desire" more of a thematic than a specific mechanic, and coming up with at least two or three distinctive behavioral traits.

[Curaigh]

Newton Philis wrote:

What appeared to be the object of your desire, suddenly comes to life as it lashes out at you with its tentacles.

Deep Desire CR 5


Congratulations on Top 16 Newton!

Visuals assume a lot of what I (the reader/the player) will be doing, but I suppose if any critter can get away with that, it is this one. Stats seem ok except for low AC and hp. This will not last long against 5th levels. Aberrations are meh for me and this ones abilities do not give it enough to be unique. In fact I would have a had time telling my players this is not a mimic.

Not in my keep pile, but not bad either.

[frank gori]

Criteria:

The Monster round is my favorite in the competition as it generally exposes the designers in a way previous rounds do not. 300 words is enough to make an impression but does not tell me much about you as a designer.

The monster round tells me about your gaming ascetic, your attention to detail, and if you have the creative chops to be different. Anyone can make a boring monster it takes a special kind of mind to make a Chimney Troll or a Yellow Tongued Hulk. IS it fair to compare you to my favorites from prior years? Probably not but I'm going to do so anyway.

Format you'll find familiar but shorter than my item reviews. I'm combining bad and ugly and I'm going to be harsh even on the things I like, this is because compliments don't make you better.

Good Ambush predator is not a bad way to go and I was looking for something like that in this round basically a manipulator.
Bad and Ugly There's a ton of creatures that can do something similar to this... It's pretty much a stple/trope for the demonic subtype.
Overall I'm not going to beat you up more here, I'm not a fan of this... D.

[Jacob W. Michaels]

The description doesn’t work for me. I understand what you’re going for, but I can’t just read this out loud at a table as each character is going to have a different desire. It leaves me pretty concerned about what the rest of this is going to be…

The write-up’s OK. This seems to be a somewhat telepathic mimic, which isn’t super exciting. It’s odd that your first example is a beetle, which is non-intelligent, but food makes some sense if they can have desires. Still, if all the PCs have different desires, this isn’t really going to throw them (not to mention if their desire is for their spouse, they’re going to be awfully suspicious when she’s suddenly in the Darklands with them). I think my favorite part was the bit about the drows, which would make them more than a wandering creature, but that’s not really enough for me.

hp =
AC -
Atk =
Dmg – (though has constrict)
Abilities +
Saves -/+

Detect desire makes sense for the monster but isn’t particularly exciting. There’s an extra comma in the power. Mimic desire similarly is what’s expected, but isn’t really exciting. Same with chameleon, though I’m not sure why undead would have no mental desires. Maybe skeletons and zombies wouldn’t (though zombies do love them some brains), but intelligent undead certainly do.

Sorry, Newton, I think there’s just not enough here for me to get behind this. It’s basically a mimic and I don’t think it’d work as an opponent for a group of PCs.

[Jeff Lee]

This is the 16th and final monster entry I've read. Initial impressions are mixed. A mind-reading shapechanger has possibilities, but there appear to be some problems with this build. Let's dig in and see what's here.

Name: Ugh. I really don't like it.

Description: I would have gone with something more concrete. There's no way that line would be read aloud to my players.

hp:Just under average for its CR.

AC: Low for its CR.

Attack:On target for its CR.

Damage:Low for its CR. Grapple and constrict tactics might make up for this.

Primary Ability DC:Little high for the CR.

Saves: Low saves are a little high, high save is low.

Abilities: There should be three even scores and three odd scores.

Feats: Not bad, but Skill Focus seems like it could have been replaced with a better choice. The thing is a shapechanger, how stealthy does it need to be?

Skills: Math checks out. Nothing wrong here.

Special Abilities:

Chameleon: Good defensive ability, though the bonus should be listed under skills for reference.

Detect Desire: Again, this ability works for what the monster is intended to do, but it lacks finesse. As pointed out by others, one isn't usually expecting their deepest desire to be sitting in a tunnel in the Darklands. What if a fighter's deepest desire is to make enough money to buy a tavern and make it a shrine to Cayden Cailean? I think the ability is too focused on a cliched theme. I'm also not sure why the DC is Constitution-based. It should be Int or Wis based.

Mimic Desire: Again, a good ability for the monster.

Background: Theme is solid, and it fits into the Nar-Voth ecology well.

Overall, its a variation on the mimic/ambush predator theme, which has been done before. I don't think it's covering new ground. I did an ambush predator, the arcane angler, as a Wayfinder submission for issue #8. It also read the minds of potential prey, and covered itself in an illusion of something desirable for its prey. When the prey got close enough, it would swallow them whole.

I think the major weakness here is that unlike the mimic and most other ambush predators, it has the lure, but nothing to seal the deal. The mimic has glue to ensure the prey doesn't escape. My arcane angler had grab and fast swallow. Ropers sap the strength of their prey. The deep desire can grab them, but has nothing to ensure it can hold them. After the initial surprise round, a party of PCs is going to beat the snot out of this thing. That's a major design flaw.

Good luck to you in the voting.

[Garrick Williams]

I honestly like the general idea behind it. It makes me think of a boggart from Harry Potter, except it becomes whatever you desire rather than whatever you fear.

But the execution leaves much to be desired. There's absolutely no mechanical crunch to its shapeshifting aside from a bonus to Disguise.

[Lady Firedove]

This was the fourth monster I read.
I'll just be giving my initial impressions:
I like the concept! Having a creature scan thoughts for desires then mimic them to lure hapless prey into its trap is creepy cool! It could definitely lead to some interesting encounters, and fun player paranoia in explorations!
Although the name fits the concept, I don't really like it as a monster name, possibly since it could be confusing at the gaming table. ("Wait... deep desire, like what he wants, or deep desire, the creature type?")
Some of the descriptive text is written in a style that doesn't quite seem to fit with standard Pathfinder bestiary entries.
It seems strong in concept on the approach, but then what? Tentacles are briefly mentioned, but what does this tentacled base form look like? How many tentacles does it have? Why doesn't it have the option of more than one slam as a full attack action? What does it do with prey once captured? Does this average-human-intelligence-level creature have any kind of society or motivation other than survival?
Many questions remain unanswered. What is written in the description is definitely interesting, but perhaps the word count should have been used on answering some more basic questions about the monster itself.
Still, it's a neat monster, and in certain campaigns and situations, it could make for quite a memorable encounter! :)

[Browman]

A well written but boring monster.

[mplindustries]

How I Judge/Disclaimer:

I'm probably not your "typical" judge of monsters. When I GM, I tend not to use pre-generated creatures and statblocks, preferring instead to build custom foes for the PCs (this is because my houserules remove, most significantly, magic items, excessive wealth, and instant, permanent debilitating effects, like instant death, ability drain, energy drain, permanent curses, etc.). However, I do, occasionally mine extant creatures for ideas, and adapt them to suit my needs.

I would say that at least 75% of the foes my PCs face are intelligent, social creatures with class levels, as I always prefer it when, 1) there is a logical reason for an encounter (I dislike illogical filler encounters when 1d4 darkmantles drop on you just for the hell of it) 2) there are multiple ways to overcome a challenge (such as parley, escape, manipulating the environment, etc.). So, for an actual, legitimate monster to interest me, it needs to have logical reasons to interact with the party beyond "they're close by and it attacks for reasons," and ideally, it needs to create a memorable interaction thanks to a strange ability or behavior pattern.

From the PC side of the table, meanwhile, I'll be judging on how fun it would to encounter this creature. Now, I don't mean "how easy it would be to defeat," I mean how dynamic and exciting facing it would be. There are tons of filler creatures already that you just beat on until someone falls over. I want something involving unusual tactics, but that wouldn't just be frustrating.
Now, on to the monster!

I don't like this creature for two reasons:
1) it's just another "gotcha!" ambush monster, which D&D has too many of already (mimics, piercers, darkmantles, lots of different plants...the list is huge)
2) it's core ability requires excessive metagaming.

On the second point, you can't know a PC's deepest desire without asking the player. So, you ask your player what the PC's deepest desire is, then, uh, they see their deepest desire. After rolling a will save (or seeing you roll in secret). They are not going to be surprised that it's actually a trick. The only way it would work is if they deliberately play into it (in which case, they'll feel unwilling to be dubious, even though it may make perfect sense to be). It's a meta-disaster of a monster. The only way you could maybe pull it off is if you routinely ask your players what their PC's deepest desires are every session, just to set up potentially using this creature, but then, you'll also need to have them encounter those desires sometimes, so they don't just assume it's always a trick...no, this is too messy to use, sorry.

[Christopher Wasko]

Brief critiques as I prep for the possibility of advancing, focusing on feedback that is hopefully new and constructive to future designs.
Decent concept, but one that resulted in a fundamentally passive monster, and one that puts a lot of pressure on the GM to boot. This also seems more the flavor for a Katapeshi desert mirage monster than a Nar-Voth monstrosity. Beyond that, the aforementioned ties to mimics and dopplegangers kind of spoiled this entry for me.
I hope to see some more originality with equal flavor next round if you advance. Good luck!