Saturday, June 27, 2015

Rage, Frenzy, and Fury: Going Berserk in Partholon

A berserker rage is a state of violent madness that can be induced through drugs, brain damage, or deliberate practice.

Rage

In a state of rage, you are filled with bloodlust and an urge for action and violence. It is difficult to concentrate or to keep patient.
  • -2 Reaction for the team. Even if you keep your mouth shut your bristling, pacing, and glaring is overtly hostile.
  • +2 to mind-based saves, including charm-type spells and monstrous fear effects. However, if an effect instills an altered state of emotion and you fail the save, this new emotion overrides your rage. 
  • Overheating: If wearing chainmail or plate & chain, you will become fatigued (-2 attack & saves). If wearing basic plate, must adjust the fit for comfort, which reduces AC -2. (But if wearing no armor or using just a shield, gain a +1 AC bonus.)
  • Difficulty concentrating on magic or delicate tasks; requires total concentration.
  • Increased risk of chance encounters; Target Number of encounter checks increases by 1 as you find it difficult to keep quiet and patient.
  • When combat begins, enter a state of Frenzy.

Frenzy

When a fight breaks out, the smoldering rage explodes into violence. Depending on the source of your Rage, a frenzy may be triggered in every combat or only under certain circumstances.
  • +2 to Attacks.
  • Upgrade weapon damage by one die type.
  • Can't shoot but can throw.
  • Resistant to mental effects such as charm and fear. (Some complex interactions happen here, noted below.)
  • Any action besides attacking the nearest foe requires a mind-based save, and the +2 Rage bonus does not apply. This includes such actions as withdrawing, fleeing, defending, casting a spell, activating an artifact, or even moving past an opponent to attack a different one. 

Resistance to mental effects in a Frenzy must be adjudicated by the referee. Some guidelines:
  • Ongoing effects continue, but new ones usually can't be introduced.
  • New effects might only be delayed until the end of the frenzy, however.
  • While in a state of frenzy, the Rage can't be overridden unless something dramatically changes the situation.
For example, a hag induces a few-based weakness in those who fail their save when they first see her. A berserker could be pushed out of Rage before entering into Frenzy. Once he enters a Frenzy, the arrival of more hags won't be able to end his Rage until it is spent. However, if the first hag doesn't appear until the berserker is already frenzying, her sudden appearance could be enough to end his Rage and his Frenzy at once, if he fails his save (which still benefits form the +2 Rage bonus).


Sources of Rage have different procedures and may alter specific interactions.

Mushroom Tea
A special concoction available for 25 silver pennies.
  • Spend 1 turn preparing with a quaff of water and a source of heat (like a torch)
  • Make a Body save (poison). Additional doses in one day will add a -2 cumulative penalty. 
  • Pass: enter a Rage for 1 hour (6 turns). Frenzy in every combat. 
  • Fail: spend 1 turn vomiting, suffer 1 damage per HD, become fatigued (-2 AP & Saves). 

Skull-cracked
Head injuries sustained when dropped to 0 hit points.
  • Always in a state of Rage. 
  • If an altered state is induced, will revert to Rage at the end of that effect's duration
  • Frenzy only when fighting humans or human-like foes

Primal Fury
A feature of the Berserker subclass of fighter
  • Invoke as a free action, in or out of combat, to enter a Rage. Frenzy in every combat. 
  • After combat, may choose to make a Body save vs fatigue to sustain the Rage, or may let it go and revert to normal state of mind. 
  • After 1 hour without combat, must choose to save & sustain or let the Rage go, as above.
  • May renew invocation at cost of 1 hp per HD.
  • Additional abilities, such as Renewed Rage and Relentless Rage, allow additional invocation of the Fury without the hp cost. 


Monday, June 15, 2015

Meditating upon the Blue Star

This is just a bit of fluff for Caelia, the cleric in our new delving team. 

When Caelia meditates, she is trained to meditate upon the image of a Blue Star. This is considered symbolic of the natural order of the cosmos. The lines, points, and vertices of the shape correspond with the humors and energy centers of the body, with the different facets of the awakened mind, and with the spheres and planes of the cosmos. It's a bit like the Kabbalistic Tree of Life, y'see.

It is through this meditation that the cleric aligns her internal energies in accord with the greater forces of the cosmos, enabling her to channel the invisible radiance that is bane to daemon and undead alike. Caelia is trained to meditate as a daily practice. She envisions the Blue Star, she recites the litany that names the spheres and segments of which the Blue Star is composed. She visualizes the correspondences and contemplates how her body and mind connect with each other and with the greater cosmic forces.

All that changed last night. Or nine days ago. Both. For the first time, she did not need to project the memorized diagrams onto the Star in her mind's eye. For the first time she did not need to visualize the correspondences one by one. Instead she perceived them as vividly as she might see her own hand in front of her face. She was marveling at this epiphany, afloat in the timeless abyss of soft blue radiance, as beyond her physical form the days slid heedlessly by.

But both rewardingly and maddeningly, Caelia came to realize that she had ventured into the shallowest waters of a great ocean. She could now perceive that there are deeper levels of revelation encoded in the Blue Star. The way its aspects interconnect, the way correspondences layer upon one another, all of this became preciously perceptible and yet tantalizingly beyond her sight.

If she is to continue this process of revelation, she must continue her crusade against the forces of Chaos and the unnatural things that lurk beyond the borders of civilization. She must continue to win glory for the name of sainted Alcidine and the sacred order that preserves his mission.

Wednesday, May 20, 2015

The Ranger - a Specialist class for Partholon

Art by Kelly McLarnon
In my concept, a ranger is a stealthy character and an indirect combatant, an opportunist and a problem-solver. I'm treating the class as taking the role normally filled by the thief in classic campaigns, because I like this flavor more. This is an updated version of the class, which continues to owe more to Aspar White of Eslen than the Dunedain of Middle-earth.

The Ranger is an expert hunter and tracker, accustomed to traveling on her own through the wilderness and living off the land. Her nomadic lifestyle makes her a figure of suspicion when she ventures into settlements, but the opinions of ignorant strangers are a small matter in her eyes. Prior to her treasure-hunting career, she patrolled the wilderness, hunting monsters before they could become a threat to innocent villagers, and occasionally collecting bounties from whatever baron happened to be nearby when she needed money.

Rangers generally see one another as affiliates in a loose network or brotherhood. Most are solitary, but some work in bands, and some carry on a family legacy. Two of the most famous names among rangers are the Watchkeepers and the Stargazers.

The ranger's combat style emphasizes speed and mobility. She exploits opportunities when they appear, and creates them when she needs them. She is not trained to fight in plate or mail.

Stealth Skills 
(The referee should roll for stealth skills, so the player cannot be sure of the result. The PC will believe she is successful until confronted with evidence to the contrary.)
Hide in Shadows: Anybody can hide if they can actually get out of sight. The ranger can attempt to hide with no better concealment than the shifting shadows of torchlight.
Hide in Wilderness: The ranger is even better at hiding in the wild. With 1d3 turns of preparation, she can attempt to conceal her entire party. If she is only trying to hide herself, roll 2 Skill dice instead of just 1. 
Move Silently: When hidden, any movement will normally give away the hiding character's position. The ranger can attempt to move without giving herself away.

Professional Skills
Listen: Use the Skill Roll instead of the normal 1 in 6 chance for listening.
Tracking: Indoors & underground, make a Skill Roll with -1 TN for each turn of delay. In the wild, use the best of 2 Skill Rolls, with -1 TN for each day of delay, rain, or snow.
Wilderness Expert: A party with a ranger gets +1 to Travel rolls, including disorientation, searching, hunting & foraging. 
Free-climb: The ranger is skilled at climbing walls and rock faces without gear or assistance. She can climb 2d6x10 feet per turn, but never more than 100 ft or faster than her Explore speed. If the roll exceeds either limit, she is unable to make progress. If the roll exceeds both limits, she attempts progress but falls from the halfway point.

Combat Skills
Ambush: If the ranger is attacking from hiding or by surprise, add +4 AP and add an extra damage die. The target can be on guard or even involved in combat as long as the ranger herself is hidden.
Dual Wielding: When wielding two weapons, the ranger adds +1 to AP and damage if Dex is 13+.
Expert Archer:  When using a bow, the ranger can choose one special attack:
  • Move and Shoot: The ranger can move her combat speed and shoot a bow without penalty
  • Sharp-shooting: The ranger adds her Skill TN to her AP. If the d20 rolls a natural 10 or less, she may hold her shot. On a hit, her damage dice can explode (i.e., if the die rolls its highest value, roll another damage die and add it to the total).

The Ranger
Level XP HD AP
Traits
1 0 1 1
Skill: 2 in 6
2 1,500 2 1

3 3,000 3 2
Skill: 3 in 6
4 6,000 +1 hp 2

5 12,000 4 3
Weapon damage: 1d8
6 24,000 5 3

7 50,000 6 4
Skill: 4 in 6
8 100,000 +1 hp 4

9 200,000 7 5

10 300,000 8 5
Weapon damage: 1d10
... +100,000 +1 hp ...
Skill: 5 in 6

Saves: +2 Physical

Edit: revised the rules for Quick-shooting.

Tuesday, May 19, 2015

The Veteran - a Fighter class for Partholon

Art by Storn Cook
As my campaign has grown, I have expanded the classes to include some subclasses. My take on the Fighter has been drawn from the original first level title, "Veteran," and I have reworked the class to emphasize this flavor in order to keep it distinct. This post is the updated version. 

The Veteran has already survived several battles before he begins his dungeon-delving career. He may have been a member of a village militia or a city guard, or may have fought in some warlord's campaign. He may come from a lineage of knights or similar warrior-lords charged with safeguarding the realm. Whatever his background, he has left the battlefield behind and turned to crypts and catacombs, hoping that his battle-skills will keep him alive long enough to collect lost treasures.

The veteran is in many ways the easiest class to play.  He doesn't depend greatly on planning and forethought (though he will benefit from both!) and with proper equipment is about as ready as he'll ever be for whatever situations come up. He can adapt to most any situation as needed, but his standard tactic (kill monsters and stay alive) is a smart choice most of the time.

Basic Traits

Guard: When a veteran chooses to fight defensively, he gets the normal +2 bonus to AC, but can also grant an additional +2 AC bonus to a nearby ally. Guard bonuses do not stack, so a given individual can benefit from only a single veteran's protection.

Overkill: The veteran is trained to fight his enemies not as individuals but as a unit. When he deals damage in excess of that needed to slay a foe, he can deliver the excess damage to another foe in reach (so long as that target's AC is no greater than the fighter's attack). He can combine his movement and attack if needed to deliver the overkill.

Martial Skill: The veteran has learned how to get optimal performance out of all manner of weapons. A fighter can:
  • wield a spear one-handed
  • throw a spear 30 ft at normal AP, 60 ft at -4 outdoors or with a high ceiling
  • charge with a spear or lance for +2 AP and x2 damage
  • set a spear or lance against a charge for first strike and x2 damage
  •  move and shoot with a bow, but lose Overkill that round
  • shoot a bow with Overkill, spending an extra shot for each additional target, but give up movement for that round
  • add his Dex bonus to AP and damage when fighting with two weapons
Expert Traits

Hero: +1 to Command and Leadership [that's Number of Retainers and Retainer Morale]

Champion: a further +1 to Command and Leadership

Daunting: Starting at 8th level, when the veteran moves to engage enemies of 4HD or less, he may force them to make a morale check.

Warlord:  By ancient custom, only the most powerful warriors could be recognized as boyars, the warlords who governed and protected the clans. Imperial rule replaced the boyars with barons who grant their position to legal heirs, but with the decay of Imperial authority, the ancient customs are being revived. A veteran who declares himself a Warlord will attract a small army of followers above and beyond the command allotted by his Charisma. If he doesn't want trouble with the local barons or Duke Bellorum, he may seek to pledge fealty or claim a domain in the wilderness beyond Imperial control. If he doesn't mind defying the authorities, he may claim existing settlements as his own, or he and his men can live as brigands and outlaws within Imperial lands.

The Fighter
Level XP HD AP
Traits
1 0 1+1 1
Guard, Overkill, Martial Skill
2 2,000 2 2

3 4,000 3 3

4 8,000 4 3
1d8 damage, Hero
5 16,000 5 4

6 32,000 6 5
Champion
7 64,000 7 5

8 120,000 8 6
1d10 damage, Daunting
9 240,000 9 7
Warlord
10 360,000 10 7

... +120,000 +2 hp ...


Saves: +2 Physical

Saturday, March 15, 2014

Mages in Partholon

Art by Victoria Frances
Magic-users have always been my favorite fantasy archetype, which probably owes to seeing Willow at an early age.  I like to present the class as more sinister and mysterious than is typical of D&D campaigns these days, and to that end I've tempered the resource-management with an edge of risk-management.    

The Magic-user did not study at some school of wizardry, and she is not to be found behind the counter of a cozy magic shop. She learned her secret lore through a years-long and often lonely apprenticeship, and her mentor may well be the only other mage she has met in her life. When her apprenticeship reached its end, she was sent forth to test her spellcraft in the real world and earn her initiation into the ranks of the Adepts. Delving into buried ruins in search of lost treasure and forgotten artifacts is very possibly the most dangerous way to begin a career, but anyone too timid to face great risk in search of great reward should never have trucked with magic in the first place!

Although there are other techniques and traditions, the default form of spellcraft is Vornish Sorcery, which channels the power of dead-but-dreaming abominations from before the dawn of time to warp reality according to the sorcerer's will. Other traditions will be presented as sub-classes.

The mage is perhaps the most challenging class to play. With forethought and planning, she has potential to overcome almost any obstacle, but if not properly prepared can wind up being frustratingly helpless. This class will perform best with a distinct goal for each delve, and with long-term goals in mind throughout the campaign. To broaden her options, the player should expect to reinvest most of her treasure into arcane projects, and might be wise to hire retainers for bodyguards. Despite all of these challenges, a well-played magic-user can eventually become one of the most powerful and versatile characters in the campaign.

Basic Traits
Neophyte: From levels 1-3, the character is tasked with proving that her apprenticeship is complete. She is independent, succeeding or failing by her own skill, but she is not yet ranked as a full member of her sorcerous tradition. Her mentor, an NPC of at least 6th level, oversees her progress and remains available for consultation and occasional aid.

At the dawn of her career, the mage has a compendium containing the spells known as the "common grimoire" (Gloaming, Protection, Scrivening, and Sense Arcana) as well as one of the signature spells of the Vornish tradition (Charm, Decipher Script, Lock, and Sleep). A talented mage with Int of 9-12 will have learned two of these spells, while a gifted mage with Int of 13+ will have learned three. As she attains each new level, her mentor will teach her an additional spell until 4th level, at which point he shall give her a final spell as a sort of 'graduation present' and initiate her as an Adept.

Arcane Lore: When the mage encounters an artifact or an arcane phenomenon (an "arcanum"), there is a chance she will recognize it, or recall similar arcana that might provide a clue as to what she has encountered. She will need to examine the arcanum in some way - this may be as simple as looking closely at an artifact, or may require some sort of interaction (which may prove hazardous). If she can pass a Saving Roll, she will gain an insight into the arcanum's nature. She might predict one of an artifact's powers, or guess a likely incantation for a magic mirror, or realize why the dungeon corridors keep changing, etc.

Failing this, if the mage has an arcane toolkit with her, she may devote a turn to analyzing the occult resonance of the arcanum. By testing how different herbs and reagents react to the arcanum's presence, she may be able to divine its nature, gaining a second attempt at the roll.

The mage may research in a library (her own or her mentor's) to seek more insights. This is an all-day project, but the roll may enjoy a bonus depending on the library's rating (larger libraries, or libraries stocked with rarer tomes, will tend to yield better results).

Scrivening: During her apprenticeship, a mage relies on the Scrivening spell extensively in order to read arcane glyphs and runes, as well as to transcribe spells into her own compendium. Even when she has not formally memorized the complete formula, enough of the spell can be recalled that she can always cast Scrivening. However, without the complete formula, she cannot completely hide herself from the Things Outside that hunger for the life-force of mages. Casting Scrivening without memorizing it first always counts as Echoing the spell. 

Advanced traits
Adept: The mage can undertake simple arcane projects such as brewing potions and researching spells known to her tradition. (She is not yet able to discover original, unknown spells.) Her mentor remains an ally, but expects his pupil to be truly independent of his expertise. Calling on him for help may require trades of services or treasure, if only as a show of respect.

Arcane Instruments: The mage can imbue her magical essence into a staff and a dagger (called a "virge" and an "athame," respectively). Each arcane instrument is a magical weapon in its creator's hand, and she can sense its direction at any distance. While she carries either instrument, other magic-users can sense her arcane power, giving her a +1 reaction bonus. She can withdraw her essence from either instrument and imbue it into a new one, but the process takes 1d6 days. She can never have more than a single virge and a single athame at any time.


Magister: The mage can now take on advanced arcane projects, such as re-creating artifacts from the lore found in her library, or discovering original, previously-unknown spells. She can also take on an apprentice to assist her in these projects.

The apprentice begins as a 0-level retainer, typically working as a lackey to earn his keep (and to pay the costs of the spells taught to him). Once he has been given the Scrivening spell, he can assist in arcane projects and will earn a half-share of experience from that work. Normally, this would be the apprentice's only source of XP, but if he accompanies the Magister on adventures, he will be likely to advance very quickly indeed! Once he has earned 1,000 xp as an apprentice, he can be initiated to Neophyte status, but it is best to ensure he has more spells than just Scrivening in his compendium!

Presence: The mage now exudes a subtle but palpable aura of power. She gains +1 to Command and Leadership [number of retainers and retainer morale], while her enemies suffer -1 morale. She also enjoys a +1 on reaction rolls, as even her enemies are not eager to provoke her.

Cantrips: So long as she carries her arcane instruments, the mage can create very minor magical effects using the potential of items on or about her person. For example, if she carries a tinderbox, she can light a fire with a snap of her fingers; if she has coins in a pouch, she can drop them from an empty hand. If she has a torch in her backpack, she could carry an open flame in her hand, but the torch would still be consumed as though burned. In general, these cantrips are more showy than useful, and their effects do not extend beyond her person.

Arch-mage: An arch-mage is a sovereign power unto herself. She may build or seize a tower to serve as her seclusium and claim the surrounding lands as her domain. Only the strongest and most confident warlords will dare to dispute her claim; most will leave her to her own affairs, or even send gifts to curry her favor. 

Upon establishing her seclusium, she will attract the attention of several would-be students: 1-12 0-level supplicants and 1-6 journeymages (levels 1-3) seeking superior training.


The Magic-user
Level XP HD AP
Traits I II III IV V
1 0 1 1
Neophyte, Arcane Lore, Scrivening 1 - - - -
2 2,500 +1 hp 1

2 - - - -
3 5,000 2 1

3 1 - - -
4 10,000 +1 hp 2
Adept, Arcane Instruments 4 2 - - -
5 20,000 3 2

4 2 1 - -
6 40,000 +1 hp 3
Magister 4 2 2 - -
7 80,000 4 3
Weapon damage: 1d8 4 3 2 1 -
8 150,000 +1 hp 3
Presence, Cantrips 4 3 3 2 -
9 300,000 5 4

4 3 3 2 1
10 450,000 +1 hp 4
Arch-mage 4 4 3 2 2
... +150,000 +1 hp 5

... ... ... ... ...

Saves: +2 vs Magic


Saturday, July 13, 2013

Status Ailments

The most common perils of a dungeon-delving career are probably injuries and death. But sometimes special effects kick in that don't kill a delver outright, but do make life a little more difficult for a while. Here are some of them.

Drain
The living dead hunger for the life-force of those still living. Any undead monster greater than ghouls and ghasts are likely to drain the living essence out of their victims. The effect is called Drain, and is normally inflicted one or two levels at a time. If the total of Drain levels exceeds the level of the character suffering from them, he is cursed to a living death.

Each level of Drain causes -1 to attacks, saves, and hit points recovered (both for spells and for any single stretch of rest & recuperation), and it blocks the highest available spell slot from being used (so with enough levels drained, you can lose all spells and it may be virtually impossible to recover hit points). Each week of complete rest reduces the Drain level by 1. If the PC goes a month without eliminating a Drain level, all remaining levels convert to permanent level loss.

A Remove Curse spell converts all Drain levels into temporary level loss (which, after you convert the attack & save stats, is usually a big improvement). A week of rest recovers one level, but going a month without recovering a level renders all remaining temporary loss permanent. XP gained while level is temporarily reduced should be recorded separately, added to the PC's total only when all temporary levels are either eliminated or converted.

Grave Rot
This ancient curse manifests the hunger of the grave, forever striving to devour the living. The victim of grave rot gains no benefits from magical healing and has only a 10% chance of recovering any hp on any given day of rest. Wounds and even minor abrasions begin to fester, so that the character soon looks and smells ghastly. Each day the character bears wounds and fails to recover hp, he loses 1 Charisma. When hp is full, he recovers 1 Charisma per day of rest.


Paralysis
The victim is helpless for 1d4+2 turns after combat ends. Any Cure spell can end this effect in lieu of other effects.

Stun
A stunned combatant can't attack, reduces speed to 1/3 normal, suffers -4 on AC & Saves, and can't focus on magic at all. This status normally lasts only a single round.

Weakness
Each level of Weakness causes -1 to attacks and damage. Weakness persists for 1d6 turns. If additional levels are added before the first levels are fully recovered, roll duration again and start the count anew. If a character suffers more levels of weakness than her level, she recovers from half when the duration lapses, and compare again the following turn.

Sunday, June 30, 2013

Arcane Lore: Echoes & Incantations

"Certain names have the power to echo across the worlds when intoned, and there are always things listening for those names to be spoken... The only thing that tethered the Children of Night to reality was their names, and each time a name was called, that tether pulled a Child closer to wakefulness... Taking the root of a name and changing it, or masking it behind foreign mortal languages enabled a sufficiently cunning priest to draw upon a fraction of a sleeping entity's might without rousing it... The Children sleep fitfully yet, and their dreams are less pleasing to them than once they were."
 -Lucien Soulban & Sven Skoog, Clanbook: Baali
Art by Vince Locke
And so I accidentally deleted this post and must reconstruct it. Or maybe it was eaten by the things that slumber beyond the bounds of time and space? Whatever. Let's see if we can improve on the original.

Traditionally, magic in D&D is a matter of resource management: memorize a selection of spells before the adventure, cast each once per day, and when you get back to town where your spellbooks are safely stored, you can change your memorization. "Once per day." It feels a little like a fairy tale, doesn't it?

But Partholon is a little less fairy tale and a little more weird tale, so I want magic to carry an edge of danger, a sense of temptation and consequence. I also happen to be fond of risk management as a game mechanic. Some brainstorming, some playtesting, and a little help from the Amazing Sam of Difficult Terrain, and we've got a fun twist on Vancian magic that continually offers players interesting choices.

Incantations & Echoes

When a spell's incantation and infra-rational formulae are memorized, that spell can be cast at any time. The first casting each day is as safe as chanting the names of dead-but-dreaming abominations in order to steal a fragment of their powers can be. A daring or desperate mage can "echo" an incantation, casting the same spell a second time, but there is always a price. The more a sleeper's deathly slumber is disturbed, the more exhausting it is to channel its dreams into the waking world, and the more difficult it is to conceal this transfer of power from the things that stalk the shadow-realm.

When a mage echoes a spell, he suffers 1d6 damage. If this damage would reduce him to 0 hp, he rolls on the Echo Table instead. Additionally, if the next chance encounter check is affirmative, there is a 1 in 4 chance that the encounter will be with a Thing From Beyond (see below).


Echo Table
2d6 Result
12 You got lucky, punk Everything is fine... for now.
9-11 Woops, something noticed! Roll again the next time you cast an Echo.
6-8 You arrogant fool! Roll again the next time you cast any spell.
3-5 Bad trip! Out of body experience or total comprehension of infinity. Either way you're catatonic. Save vs Magic each morning to see if you come out of it.
2 Ye gods, no! Devoured by invisible demons, or yanked to a higher plane. Either way you vanish. Roll for resurrection survival: if you pass, most of you comes back.

You may notice that this is frankly just a modified Reaction Roll. I like to get more mileage out of existing resources rather than compounding the number of charts I have to keep track of.

Clerics and Others

Clerics channel their power from the cosmic spheres and the higher planes, and Druids invoke the spirits of the natural world and the twilight realm of faerie, but the mechanics of echoing spells remain unchanged. Other spellcasting classes have not yet appeared in the campaign.

Things From Beyond

This is the perfect time to throw in any wild, weird, and awesome monster that just doesn't have a place in the normal campaign milieu. Sleestaks, xenomorphs, terror dogs, splugorth, mind flayers and beholders: whatever you've always wanted to use without making it a part of the world. If you're using this echoed spell concept in a more d&d-traditional or even a gonzo campaign, there's still plenty of room for eldritch weirdness. Use the Psionic Encounters table from the 1e DMG, make a Realms of Crawling Chaos encounter table, use the stat-block for an invisible stalker and play it like the Predator - this is a chance to go outside whatever your campaign's normal boundaries may be without consequence. Even a silly encounter with flumph philosophers in the middle of a grim & gritty adventure can work out just fine as long as the creatures are clearly manifesting from outside the campaign world.