The Theory and Use of Gates in Campaign Dungeons, Part 2: On the Destruction of Gates; and, New Magic-User Spells

“And lo!---the fourteen gates of Pesh were sundered and disjoined.  And a great Nothing rippled across the plains, swallowing them in utter blackness, and carving the deep abysses that lay there now, where once the Marshals of Law marched against the multitudes of Chaos.  Only their echoes remain---forlorn and lost, beyond the edge of time.”

--- “The Fall of Aaqa” in The Fables of Burdock

Continued from Part 1: Setting the Stage.

On the Destruction of Gates

Player characters often seem to need to destroy gates and portals, prior to Something Wicked This Way Coming, in one form or another.  This brings up an interesting query, namely, how is a gate destroyed?  A number of possible means to destroy gates immediately leap to mind, including:

• hit it with lightning bolts, fireballs, ice storms, cones of cold and whatever other attack spells are available
• disintegrate it
• shatter it
• destroy the gate’s grounding frame/location/henge, for without its moorings, the gate cannot exist and dissipates into wisps of nothing
• open a second gate within the first gate (the Babylon 5 solution)
• destroy all of the portals leading to/from the gate (the Morgaine solution)

Some or even most of these methods may not be available to most PCs, however, while others offer little to no hope for the characters to continue on in their current setting (C. J. Cherryh’s Morgaine regularly travels from world to world, closing each gate behind her---never able to return to her home or to travel back from whence she came).  I recommend that you make the methods of destruction for each gate unique, but also remain flexible to allow player ingenuity to provide inspiration.  That way you can roll on the table below once the gate has been nuked successfully!

d100          Result

01-55         Nothing:  the gate is destroyed with no ill effects or unintended consequences

56-73         Explosion causing 6-15 d6 damage (roll 3d4+3 d6s) to all within a 50’ radius
                  (unmodified save vs. Breath Weapon for ½ damage); reduce damage by 2d6

                  and extend radius in 50’ increments until no further damage dice remain;

round down to 0 if only 1 die remains for the final 50’ radius increment)

74-79         Implosion:  everything within the radius is sucked into the singularity and

destroyed; roll d100 again for specifics:

d100    Result

01-70   Small and slow implosion in a 0-40’ radius:  ([2d6]-4) x 5’; 1 in 20

small implosions result in the creation of a sphere of annihilation

71-100  Large and fast implosion in a 50-5000’ radius:  (5d100) x 10’; 1 in 3

large implosions result in the creation of a sphere of annihilation

                  Small implosions allow 1 segment of reaction time per 10’ of distance from

the gate; large implosions allow 1 segment of reaction time per 1000’ of

distance from the gate.  Gentle and Benevolent DMs may allow PCs

unmodified saving throws vs. Breath Weapon to avoid destruction, in which

case each PC is cast into a random plane and each item in their possession

must make an unmodified saving throw vs. disintegrate or not survive the

implosion. 

80-88               Spatial/Temporal/Planar Distortion:  the space-time continuum and the megaflow buckle in response to the destruction of the gate:

d100    Result  
01-34      PCs are randomly plane shifted to somewhere across the span of 
               planes that the gate normally traverses
35-49    Space in a (4d6) x 10’ radius warps into non-Euclidean geometry
50-77    Space in a (6d12) x 10’ radius is distance distorted and slowed
78-90    PCs remain in place but are thrown forward or backward in time (roll 1d6 three times, for Results 1, 2, and 3):

d6       Result 1       Result 2        Result 3                Result 4

1         1d3                    days                 historical past        feet

2         2d6                   weeks              normal future        yards

3         4d12                 months           alternate past         fathoms

4         8d24                years                alternate future     furlongs

5         16d30              centuries         bizarre past            miles

6         32d100           millennia         bizarre future        leagues

91-97   A reality maelstrom is unleashed, centered on the previous

location of the gate; roll 1d4 on the table above for Results 1 and 2

to determine its duration

98-99      1d3-1 planes associated with the gate begin to bleed into the

plane where the gate was destroyed:  matter, flora, and fauna,

“invade”; if a 0 is rolled, planar matter from the location of the

gate bleeds away into the newly-adjacent plane; duration and extent of the bleed is based on 1d4+1 for Results 1, 2, and 4 above

100      Roll twice.  Do not ignore subsequent rolls of 100. 

80% of the distortions above are temporary in nature, and will fade within (roll 1d6 for Results 1 and 2 on the time travel table).   

89-100           Planar Rift:  the planar boundaries are rent, and a new planar geography begins to emerge in response to the destruction of the gate:

d6         Result

1                     The plane splits in two, over the span of (roll 1d6 for Results 1 and 2 
              on the time travel table above)

2                    The plane fragments into 2d4+1 planelets, over the span of (roll 1d4 
              for Results 1 and 2 on the time travel table above)

3                    An area spanning (1d3+3 Results 1 and 4 on the time travel table above) sloughs off as a new demi-plane, in (1d3 Results 1 and 2)

4                    The gate is not destroyed, but is instead amplified as a fixed conduit 
              to a single destination; the gate’s size increases to (1d3 for Results 1 
              and 4 above)

5                    The gate’s destruction triggers a planar collision, as 98-99 planar 
              bleed above, but more widespread and catastrophic in nature:  the 
              geographies of the planes smash together, their atmospheres mingle, 
              earthquakes and volcanoes arise in response, etc. (think of this as 
              planar plate tectonics:  eventually one plane will grind another away, 
              or perhaps they’ll simply bounce apart in time…)

6                    The gate’s destruction triggers a multi-planar collision, in which 
              2d4-3 planes collide; for any result of 0 or less than zero, treat this as 
              a planar-wide implosion over the span of as the plane collapses into 
              itself over (roll 1d3+1 for Results 1 and 2)

80% of the rifts above are permanent in nature; if temporary (and actually reversible), they will fade within (roll 2d3 for Results 1 and 2 on the time travel sub-table above). 

I encourage all Dungeon Masters to let loose the hounds of insane imaginings when modifying this table for use in your own campaigns!

New Magic-User Spells

“I have analyzed the dweomers, notes, and formulae within Yagrax’s tome, and extracted herein those that bear the most promise for further development.  While his efforts demonstrate his facility for conjurations, he is clearly building upon key principles that enable gates to function.  These laws are the foundational elements through which we travel the multiverse---Keoghtom clearly mastered these precepts when he forged his rod, but from what sources did he and Yagrax gain their knowledge?  I must find their original source---even if from Gresil, and no matter his price.”

--- The Witch of Perrenland, The Demonomicon

If you want to establish gate-related magics as more-readily accessible in your campaign (as when playing in Michael Moorcock’s Eternal Champion multiverse, or in Philip Jose Farmer’s World of Tiers settings, for example), consider reducing the level for all of the following spells by one (i.e., Detect Gate becomes first level, Identify Gate second level, etc.).  Similarly, if gates are wondrously rare artifacts in your campaigns, feel free to raise the level of the spells by one (Detect Gate becomes third level, etc.).   In my campaigns, Identify is a second level magic-user spell, which is why Identify Gate is one level higher than Detect Gate to begin with.  In addition to deciding how to adjust the spell levels in your campaigns, you may want to consider the rarity of these spells.  Again, in my campaigns, I assign scarcity to all named spells, as well as various others based on how I manage magic in the campaign:  spell frequency follows that of monsters---Common (65%), Uncommon (20%), Rare (11%), Very Rare (5%), and Unique---and I generally assign all spells new to the campaign a frequency at least Uncommon, if not perhaps Rare or Very Rare.  PCs may need to discover these spells from the long-lost spellbooks of ancient mages, or to perform a geas or quest for the order that guards their secrets.  Drive the availability of the spells by how common the knowledge and workings of gates will be in your campaigns, because these tools strongly empower PCs to break the “broken” spells:  for example, using force gate, a PC can trail a foe who fled “to safety” via dimension door or word of recall or similar escape magics.

New Magic-User Spells

Second Level:  Detect Gate

Third Level:  Identify Gate

Fourth Level:  Dimensional Anchor, Gatetrace

Fifth Level:  Force Gate

Sixth Level:  Dimensional Lock

Detect Gate (Divination)

Level:  2 (and see below)

Range:  0

Duration:  1 round/2 levels

Area of Effect:  1” wide path, 1” long/level

Components:  V, S, M

Casting Time:  1 round

Saving Throw:  None

This spell enables a magic-user to scan for gates and teleporters; in a manner similar to detect magic, up to 60 degrees may be scanned each round, out to a range of 1” per level of the caster.  Detect gate also detects extra-dimensional pockets (rope trick, Leomund’s Tiny Hut or Secret Chest, a portable hole, etc.), astral spell, maze, Murlynd’s Void, phase door, plant door, prismatic sphere or wall (so long as the violet layer remains in effect), shadow door, shadow walk, transport via plants, and similar magics, as well as a sphere of annihilation, amulet of the planes, cubic gate, well of many worlds, etc. if such magic items are within range and actively in use.    It will not detect monsters existing in more than one plane (level-draining undead, for example), lesser conjurations (monster or animal summoning, beckon, implore, etc.), spatial warping effects (displacement, distance distortion, reverse gravity, etc.), or other near-instantaneous gates (Chariot of Sustarre, plane shift, prismatic spray; see below also on recency, however).  If any detectable objects are present within range, the caster will know their relative numbers and relative distances within scanning range (i.e., “You discern two teleporters to the SW at 5” and 9” ranges, and a gate 25 feet away in the same direction”).  Detect gate is blocked just as other divination magics are (by 1/12” of metal, 1’ of stone, etc.), with the caveat that very strong (or more powerful) gates may sometimes be detected even through thick stone walls or perhaps even through lead. 

The spell also allows a base 10% for each level above 3^rd for the caster to determine one or more of the following outer traits about a detected teleporter or gate.  Some gates are easier to detect  based on the intensity of their auras, as well as their recency of usage (see below for modifiers); some magic items may also boost these detection percentages.  Each outer trait requires one round of concentration with no further scanning for the presence of gates; the caster may attempt to detect one outer trait per round, and must begin with intensity, although subsequent rounds of detection may occur in any order desired:

• intensity:  a measure of the strength of the gate’s magical and planar auras and connections; detection levels are:  none/inactive, dim, faint, moderate, strong (detects +10%), very strong (detects +25%), intense (detects +50%), overwhelming (detects +100%)
• recency:  a measure of the when the gate was most-recently used last; detection levels are:  fresh (used within 1 round/level; detects at +50%), recent (within 1 turn/level; detects at +25%), waning (within 1 hour/level, detects at base), dwindled (within 1 day; detects at -25%), stale (within 1 day/level; detects at -50%), lapsed (within 1 week/level; detects at -75%), atrophied (within 1 month/level; detects at -125%), eroded (within 1 year/level; detects at -200%)
• ethos:  a measure of the alignment components of a gate’s destination(s) (if any); detects as:  none, law, chaos, good, evil, neutrality (no detection modifiers)

If a caster fails the roll, they may receive no reading, or perhaps misinformation about the trait sought---“dim” detects as stronger; while “law” and “good” ethoi result in opposed values or read as none perhaps; recency resolves as at least two places removed from actuality, etc.---DMs must adjudicate such instances. 

Some clerics are able to cast detect gate as a third level clerical spell if it fits within the portfolio for their deity; however, like detect magic, most clerical casters are not able to divine more than the presence or absence of a portal, and they cannot discover any of its outer traits.  The material component is a small platinum tuning fork, carefully fashioned to vibrate when gates are detected (cost 800 gp; the ‘fork is reusable). 

Identify Gate (Divination – Conjuration)

Level:  3

Range:  ½”/level

Duration:  1 segment/2 levels

Area of Effect:  One gate or teleporter

Components:  V, S, M

Casting Time:  1 turn

Saving Throw:  Special

This spell allows a magic-user to identify one or more inner attributes about a gate, teleporter, or similar magical transportation feature (pool, archway, etc.).  Note that unlike the first level spell identify, the magic-user is not required to touch or to directly handle a gate or teleporter since the spell may be cast at range (albeit a very short one).  The caster has a base 20% chance to identify an attribute, plus 5% per level above 5^th.  The caster may attempt to identify one or more of the following attributes of a gate, in any order, at the rate of one trait per segment:

• activation method(s):  general details about how the gate is activated---by walking through, by command phrase, by proximity of some sort of key or item, by ritual, etc.; specific details beyond walking through the gate often require research via consultation with a sage or bard, legend lore or contact other plane, or similar efforts to glean the full information
• destination(s):  the caster discovers how many destinations to which the gate leads; if the gate can access more than one plane, planes will be identified from most- to least-commonly travelled destinations
• periodicity:  determines if the gate is always on, or periodic; a second check will determine the frequency of the gate’s operative periods---every other round, once per day, upon command, during the new moon, etc.; a third check will determine the duration for the gate’s activity cycle---always on during the full moon, one use during a full moon, for one hour after the third person to walk through during a full moon, etc.
• sweetness:  a measure of the discomfort that passage through a gate causes, based on a 14 Constitution; adjust upward or downward from Con 14 using detect gate’s intensity scale to determine PC impact, if any:  none (no effect; the gate is “sweet”), faint (mild dizziness), moderate (dislocation), strong (mild nausea), very strong (nausea), intense (strong pain), overwhelming (unconsciousness); each level of effect is cumulative, and exact effects are left to the DM to adjudicate
• symmetry:  does the gate shift travellers’ physical positions during transit, or do they arrive in the same positions relative to one another, to the gate itself, etc.
• temporality:  does the gate shift travelers forward or backward in time, or have a discernable lag during transit time
• cardinality:  is the gate one-way or bi-directional?
• traps*:  the caster identifies one trap on the gate, if any, along with the trap’s level of threat (use detect gate’s intensity scale)
• usage restrictions:  identifies whether or not the gate restricts usage in some manner, such as by home plane, race, sex, alignment, class, level, eye color, family lineage, etc. ; the first check provides a yes/no response, while subsequent checks provide one restriction per check

After casting the spell, and determining what can be learned from the gate, the magic-user loses 8 points of Constitution, and must rest for 1 hour per point in order to regain them.  (See the first-level spell Identify for further effects of Constitution loss). 

The material component of this spell is an alchemical infusion that consists of a 500 gp violet garnet, which is powdered by the magic-user and then mixed with red wine and the ocular juices from a roc, giant eagle, ki-rin, beholder, or similar creature with far-seeing and/or magical vision.  The component must be drunk (and is consumed) with each casting of the spell.

* If detect traps (Cleric 2) is cast on a gate, most clerics will have a 7% chance per level above 3rd to detect if a magical or mundane trap exists on a gate, with a maximum chance of 63% at 12th level.  Some clerics may have higher or lower chances, depending on their deities’ spheres of influence. 

If a thief, thief-acrobat, assassin, monk, or bard attempts to Find Traps upon a gate, such PCs have their usual chance to determine whether any small, physical traps exist on a gate and its associated housing (if any).  For gates with an intensity or sweetness of strong or greater, the PC may suffer a penalty to their ability, due to distraction caused by the gate’s aura.

Dimensional Anchor (Alteration – Conjuration/Summoning, Abjuration)

Level: 4

Range:  2” plus ½”/level

Duration:  1 turn/level

Area of Effect:  One to four creatures

Components:  V, S, M

Casting Time:  5 segments

Saving Throw:  Negates

This spell prevents target creatures from employing extra-dimensional travel.  The caster may select up to four creatures as targets, and those that fail their saving throw are limned with a deep emerald aura.  If three or four creatures are targeted, each saving throw is standard; targeting two creatures reduces saves by -1; if a single creature is targeted, it saves at -3.  Forms of movement barred by a dimensional anchor include the usage of astral spell, blink, dimension door, displacement, etherealness, gate, maze, plane shift, phase door, rope trick, shadow walk, teleport, and similar spell-like abilities or magic items (including the usage of free-standing gates and teleporters, bags of holding, cubic gates, portable holes, etc.).  A dimensional anchor does not interfere with the physical movement of affected creatures, or affect creatures already in ethereal, astral, or shadow forms when the spell is cast.  The spell does not block extra-dimensional perception or attacks including the ability for undead to energy drain, nor does it prevent summoned creatures from disappearing at the end of a summoning spell’s duration.  The material components are one 3” long pin formed from adventurine (green quartz) per targeted creature, as well as a swatch of fine, earthen-hued silk, into which the pins are stuck.  The fine silk costs 25gp, and is consumed in the casting; each pin costs 250gp, and may be reused.

Gatetrace (Divination – Conjuration)

Level:  4

Range:  3”

Duration:  Special

Area of Effect:  one portal

Components:  V, S, M

Casting Time:  4 segments

Saving Throw:  None

This spell informs the caster of the destination for the last usage of any gate or teleporter, including the destinations for the residual and temporary portals created by spells like dimension door, plane shift, teleport without error, a ghost or phase spider entering the Ethereal Plane, psionic Probability Travel, etc.  In order to trace the destination of a non-permanent gate, the caster must first employ detect gate to identify where to focus the gatetrace spell (if detect gate was unsuccessful in determining a gate’s intensity, recency, or ethos, gatetrace will provide aligning, although equally incorrect, information).  The destination is given as a plane, as well as a complex string of multi-planar coordinates, which can be used to arrive at the same destination if the caster has some form of appropriate magical transport available (dimension door, teleport, gate, etc.).  The coordinates remain in the caster’s memory for one round per level of the caster, and may be transcribed by the caster for future usage if he or she does not currently have an appropriate spell memorized or device to enable immediate travel to the destination.  Coordinates require 1d4 rounds plus a varying amount of time to transcribe, based on the following table:

Destination is Within	Transcription Time
Prime Material Plane	no additional time required
Demi-plane or other non-standard Prime Material Plane location (other planet, etc.)	+1 round
Alternate Prime Material Plane	+2 rounds
Demi-plane or other non-standard Alternate Material Plane location	+3 rounds
Ethereal Plane	+2 rounds
Elemental or Quasi-Elemental Plane	+3 rounds
Other Inner Plane (Shadow, Positive or Negative Material, Concordant Opposition, etc.)	+4 rounds
Demi-plane within Inner Planes	+5 rounds
Astral Plane	+7 rounds
Demi-plane within Astral Plane	+9 rounds
Outer Planes – The Abyss, Pandemonium, or Limbo	+16 rounds
Outer Planes – all others	+10 rounds
Demi-plane within The Abyss, Pandemonium, or Limbo	+24 rounds
Demi-plane within all other Outer Planes	+12 rounds
Another Multiverse	+ 30 rounds

Instantaneous communication of the coordinates string is possible using telepathy, ESP, Rary’s Telepathic Bond, etc. and the various Extension spells will allow the coordinates to remain in the caster’s memory for a longer duration, of course.  The material component for the spell is a pair of 5” by 1” electrum bars, beaten wafer-thin and finely polished on one side; the two are twisted into an infinite loop during the casting of the spell, with the reflective sides facing each other across the middle of the ouroboros helix.  The component costs 400gp and is consumed in the casting.

Force Gate (Alternation – Conjuration/Summoning)

Level:  5

Range:  3” + ½”/level above 11^th

Duration:  Special

Area of Effect:  one portal

Components:  V, S

Casting Time:  3 segments

Saving Throw:  None

Force gate allows the caster to force open (to fissure) and activate a gate that is inactive or that is otherwise unusable by the caster, whether due to unknown activation methods, pre-specified times only during which the gate will function, being on the wrong side of one-way transit options, or due to other usage restrictions.  The spell affects permanent and temporary gates, including those portals created by abjure, word of recall, transport via plants, blink, dimension door, maze, astral spell and similar transportational and conjuration/summoning spells and magic items.

In general, the forced gate remains open and available to use for 1 turn plus 1 turn per level above 11^th; during that time it can be used normally by any creature, with our without the presence of the caster.  For spells with instantaneous durations, such as teleport without error, the forced gate remains open for 2 rounds plus 1 round per level above 11^th.  The spell functions for just one side of a portal:  thus, if an MU and party pass force a gate and pass through to the other side, the first casting of force gate will not allow them to use the gate to return unless it is normally available for their usage.

Note that there is no material component for this spell. 

Dimensional Lock (Alteration – Conjuration/Summoning, Abjuration)

Level:  6

Range:  ½”/level

Duration:  1 day/level

Area of Effect:  Special

Components:  V, S, M

Casting Time:  1 hour

Saving Throw:  None

This spell creates a shimmering emerald ward that prevents extra-dimensional travel into or out of the area of effect.  The caster may effect up to a single 40’ cube in volume, plus another 40’ cube per level above 13^th.  All forms of movement barred by the fourth level spell dimensional anchor are warded against by a dimensional lock.  In addition, a dimensional lock prevents the physical crossing into the area of effect while in an extra-planar form (ethereal ghosts must materialized in the Prime in order to cross into a dimensionally locked room, for example).  It also blocks extra-dimensional perception into the prescribed area of effect, so that ethereal creatures, for example, cannot see into the area of effect, nor could cross-planar scrying originating from outside the plane of the warded area.  Once the dimensional lock is in place, it may be concealed or be built-over---such cosmetic changes do not impair its protection.  Dimensional lock may be made permanent.

Some variations on dimensional lock allow the caster to designate creatures present during the casting of the spell to be immune to the dimensional lock, and therefore they are permitted to travel into and/or out of the circumscribed area while others cannot.  The material component may take a variety of forms, depending upon the exact application of the spell in the target environment; in general, the material component consists of four gallons of a magical paint, wash, or mortar, which outlines the protected area to be warded.  The formula for the planar sealant requires three months to distill per 40’ volume affected, and costs 640 gp---but ten times that if the spell is to be made permanent!.  It is consumed in the casting of the spell. 

Various other gate-related magics have been rumored to exist, or to have been used by mages prior to the twin cataclysms.  Such legends speak of mages who temporarily blocked a gate’s functionality, and who diverted the gate to an unexpected destination (to catch a pursuer unawares); wizards would peer through a gate to scry all of its destinations, and bind gates into servitude.  Others could track and follow a creature fleeing across the planes, no matter how many gates and planar changes to its destination.  Archmages would banish one or both terminuses of gate, and could hide a gate, even one of overwhelming intensity.  These spells are just the beginning---the possibilities are, of course, endless!

Look for another new gate-related spell in The Twisting Stair #2 (Summer 2017):  The Multi-Faceted Portal-Penetrating Gaze, a level 4 Magic-User divination spell.

Allan.

"The Theory and Use of Gates in Campaign Dungeons, Part 2:  On the Destruction of Gates; and, New Magic-User Spells" first appeared in Knockspell Magazine #4 (Spring 2010).