DW Monsters: Slitheen

Next, we reach Aliens of London, which introduces us to the Slitheen. These turned out to be memorable, often being referenced in later stories, although only being the focus of one other, Boom Town, later on in the same season. They (or members of their species) have, however, also had major roles in three episodes of the Sarah Jane Adventures, as well as two original novels, and four audio releases to date – the latter including one Torchwood release and one other not featuring the Doctor. 

It may also be worth noting that the alien race the Foamasi, from the Fourth Doctor TV story The Leisure Hive, are essentially the same concept as the Slitheen, although they look quite different out of their skin suits and lack the biological peculiarities. They’ve proved less popular, only re-appearing in one of the ‘90s novels.

Description and Biology

The Slitheen are, of course, an organised crime family, not an alien race per se. The species they belong to are called the Raxacoricofallapatorians, which rather explains why the family name gets used more often. The Raxacoricofallapatorians are large hairless humanoids with long claws, large eyes, and arms much longer in proportion to their bodies than is true of humans. 

Despite their roughly humanoid form, Raxacoricofallapatorians are biologically quite different from humans and, in many respects even from, say, Silurians or Sontarans. They are said to be largely made of “calcium phosphate”. This is a rather vague term, referring to a number of different chemicals – one of which, hydroxyapatite, is the primary mineral component of human bone and tooth enamel. It’s not at all obvious how an apparently organic being could be made out of what is essentially a mineral salt and still less why they would react explosively with vinegar if they were (calcium phosphates do dissolve in acetic acid if left for long enough, but you may have noticed that your teeth do not explode when you eat a pickled onion). But we’ll let that pass.

The large, dark eyes would imply strong night vision, although an official webcast suggested that they were for vision in blizzard conditions rather than a product of a nocturnal lifestyle (not that I'm sure why that would work). They are also said to have a remarkably keen sense of smell.

Since they don’t wear clothing when out of their skin suits, we can also make some speculations about their biology. For instance, males and females look much the same, so it seems unlikely that they are mammalian. They also appear to lack any external genitalia. One possibility here is that they use external fertilisation in a pool of water, as some amphibians do, but another is that the male’s intromittent organ is retracted into a protective pouch when not in use. We know that they lay eggs although it’s interesting that they also possess what looks like a navel. Although it’s not impossible, depending on the structure of the egg, this is not what we’d expect in an oviparous animal – but it could be that it is an orifice of some kind and not a navel at all.

Game Attributes

Given their greater-than-human size and disproportionately long and muscular arms, we can safely say that Raxaocoricofallapatorians are significantly stronger than humans – likely even an “average” member of the species would be around the maximum unmodified human strength. They are also physically resilient, although perhaps not exceptionally so for their size. The long claws on their fingers make it unlikely that they are highly dextrous when it comes to fine manipulation, but they move quickly and are more agile than they might appear. Presumably, their mental attributes are similar to those of humans since there seems little to indicate otherwise.

For our purposes, the typical member of the race we’re going to stat out here is a low-ranking member of the Slitheen family. Doubtless, this is not typical of Raxacoricofallapatorians as a whole, since they must have numerous shopkeepers, accountants, mechanics, and all the various other jobs that keep an advanced civilisation ticking over but it’s the Slitheen we’re primarily interested in here, and they (or some of their close relatives) are likely to be how the race is most often encountered.

Taking that approach then, we’re looking at somebody who is basically a low-level scavenger/hoodlum. Their combat skills are likely to be reasonable, although we don’t really see them using guns (difficult with their hands, perhaps) so it’s most likely hand-to-hand combat, albeit aided by claws that are basically swords. Their other skills will be based on intimidation, dealing with the criminal underworld, and technology with a particular emphasis on anything that lets them get past security. Despite this “rogue”-like part of their skill set they don’t seem especially stealthy and they certainly aren’t going to be able to pick pockets in their regular form. Given their modus operandi, we can also say that they must have good social and acting skills to fool members of other species into thinking they are something they are not.

Special Abilities

In addition to their purely physical traits, the Slitheen are notable for a couple of particularly useful features. Firstly, there’s the ability to disguise themselves as humans. This uses advanced technology, rather than anything innately biological, but it’s notable that, while inside the skin suit, they can move no faster than regular humans and we’d expect their strength to scale down accordingly as well. There’s no real reason to suppose that their statistics would otherwise change, however.

The second feature is that females of the species can create poison darts in their fingers that they can fire at threats. From what we see, these don’t have an especially long range and would be best used close-up. We don’t know how effective the poison is, but there seems little point in it if it isn’t at least debilitating to a human-sized target, perhaps similar to snake venom.

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5E - Slitheen

Large humanoid, neutral evil

Armour Class: 12 (natural)

Hit Points: 45 (6d10+12)

Speed: 40 ft.

STR 18 (+4)	DEX 12 (+1)	CON 14 (+2)
INT 10 (+0)	WIS 10 (+0)	CHA 12 (+1)

Skills: Deception +2, Intimidation +2

Damage Vulnerabilties: acid

Senses: Passive Perception 10

Actions:

Claws. Melee Weapon Attack: +3 to hit, reach 10 ft., one target. Hit: 9 (1d8 +4) slashing damage.

            Dart (females only, once per long rest). Ranged Weapon Attack: +3 to hit, range 20/60 ft., one target. Hit: 1 piercing damage, and the target must make a DC15 Constitution saving throw, taking 7 (2d6) poison damage on a failed save, or half as much damage on a successful save.

Challenge: 1/2 (100 XP)

BRP - Slitheen

STR 2D6+12 (19)	CON 2D6+6 (13)	SIZ 2D6+12 (19)
INT 2D6+6 (13)	POW 3D6 (10-11)
DEX 2D6+6 (13)	CHA 3D6 (10-11)
Hit Points: 16	Move: 15
Base SR: 4	Damage Bonus: +1D6

Armour: 1-point leathery hide

Skills: Appraise 40%, Disguise 80%, Fast Talk 40%, Jump 40%, Repair 40%

Combat Skills: Brawling 60%, damage: 1D8+1D6

Dart (females only): Missile weapon attack, range 10, 1 point damage plus POT 10 poison.

GURPS - Slitheen

ST 18	DX 12	IQ 10	HT 12
Thrust: 1d+2		Swing: 3d
Speed: 6		Move: 8
Size: 1

Advantages: Alternate Form, Alternate Identity, Claws (Long Talons), Damage Resistance 1, Discriminatory Smell, Innate Attack 2 (females only, toxic, reduced range/2, resistible)

Disadvantages: Enemies (rivals), Greed, Reputation (criminal), Vulnerability (acid)

Skills: Acting-14, Brawling-14, Computer Operations/TL10-11, Electronic Operations-10, Fast Talk-12, Innate Attack-13, Intimidation-13, Streetwise-11

Savage Worlds - Slitheen

Agility: d10	Smarts: d8	Spirit: d8
Strength: d12	Vigour: d10

Skills: Electronics d4, Fighting d6, Intimidation d6

Edges: Fleet Footed, Streetwise

Hindrances: Wanted (minor)

Powers (females only): Bolt

Special Abilities: Claws, Environmental Weakness (acid)

Pace: 8                  Parry: 5                 Toughness: 9                      Size: 2

STA - Slitheen

Control: 8	Fitness: 12	Presence: 9
Daring: 9	Insight: 8	Reason: 8
Command: 0	Security: 2	Science: 1
Conn: 0	Engineering: 1	Medicine: 0
Stress: 14	Resistance: 0

Claws: Melee, 2^, Vicious 1

Dart (females only): Ranged, 1^, Deadly

DW Monsters: Gelth

The third story in the revised series is The Unquiet Dead, for which the alien menace are the Gelth. They are a one-off monster in the TV series, and, apart from a few minor mentions here and there, have only appeared once since, and that in a short story, rather than anything more substantial.

Description and Biology

We are told that the Gelth were originally regular organic beings. They somehow lost their physical bodies during the Time War, becoming gaseous instead. How this would work is obviously unclear, but, in fairness, we have little idea from the TV series of how exactly the Time War was fought or what the weapons brought to bear in it were capable of.

Either way, the Gelth as they are now are gaseous wraiths, capable of creating partially humanoid shapes, but generally not bothering to do so. The evidence suggests that are composed of organic gases; they can survive without difficulty in natural gas, which is mostly methane, so it’s unlikely they contain much of that or they’d diffuse away, but ethane, propane, butane, and more complex hydrocarbons may all be involved. Biologically, it’s hard to see how this could possibly work, at least in Earth-like conditions, so a more likely explanation is that the body is somehow held together by force of psychic will.

Which is basically saying “it’s magic”, rather like the air elementals of fantasy games, but it’s what we’ve got.

The Gelth can control and move their gaseous substance around which, in the context of the story, means that they can inhabit the putrefying gases inside a human corpse and make it move around. Their preference for humans here, since any other animal would surely also work, is likely a simple matter of availability, given where they happened to appear. Assuming that they were originally humanoid, as the briefly-seen blue form implies, there’s probably also an improved degree of familiarity with the form that makes it easier (and arguably more useful) for them to animate a human cadaver than, say, a dead rat.

We know essentially nothing of Gelth society and culture, beyond the fact that it was destroyed in the Time War. We don’t know whether they breathe or how they obtain energy although whatever they do it’s likely not obvious – obtaining energy from the air molecules around them, say. Lacking any actual sense organs, we’re again left with psychic powers to explain how they navigate the world around them; perhaps the ‘real’ Gelth are purely psychic constructs that find it easiest to interact with the environment by controlling gas molecules. Although, if so, the molecules must act as a necessary tether, since destroying them (by combustion) kills the Gelth and prevents it from reforming.

How, and even if, Gelth reproduce is equally mysterious. Potentially, it could be an ability that they lost when they lost their bodies, although with “billions” of them supposedly still in existence at the time of the TV story, that must have been a recent event for them – for whatever that means in the Time War.

Game Attributes

While inhabiting human bodies, the Gelth are essentially zombies, a concept familiar in many fantasy games and echoed a few other times in Doctor Who itself. We can see that they move slowly and clumsily, doubtless due to the difficulty of the Gelth controlling the host body, and there’s no evidence to suggest that they are any physically stronger than they were in life. They likely are physically resilient, however, being unable to bleed to death and having no vital organs since they are animated purely by the putrefying gases inside them. Similarly, they won’t feel pain, since even if their nerve endings are still functional (which seems unlikely) the Gelth isn’t actually inhabiting their nervous system and wouldn’t receive any signals from it. Destroying the zombies is instead a matter of somehow getting the gas to leave the body or destroying enough of it that it’s no longer functional.

Depending on the game system, this could be quite difficult or just a case of knocking a few hit points off.

The Zombies seem unintelligent, partly because the Gelth don’t seem to have enough control of their vocal cords to be able to speak. Logically, this is something they could get the hang of with time, since gas moving about is rather how speech works, but gaining the necessary fine control evidently isn’t a simple process. Nonetheless, while it may appear stupid, the zombie is directly controlled by a Gelth, and these are presumably no less intelligent than the average human – and their leaders likely more so. Some remnant of the original soul apparently remains, but the Gelth seem to be able to force it down with a little effort.

There’s also the question of the Gelth in their natural form. Here, they appear agile but have a physical strength no more powerful than a breeze, likely at the very minimum that a given system will allow. How difficult they are to destroy depends on how strongly the animating force can hold the molecules together and, from everything we see, that’s pretty tough. Physical attacks aren’t going to do anything to them, so we’re left with psychic assaults and effects that might change their chemical composition. The obvious example here is combustion, since we know they are flammable, and this seems a particularly high vulnerability. (When it comes to D&D, it’s worth noting that lightning attacks would probably also ignite them).

They probably can’t be poisoned, even with other gases – unless, perhaps the ’poison’ reacts with their hydrocarbon molecules to make something they can’t control. But this isn’t necessarily an issue in plausible conditions. For example, while hydrocarbons react with chlorine, the result is usually still a gas, which the Gelth may not have any problem animating… although they’re likely to smell worse as a result.

Lack of any knowledge of their culture makes it harder to say what skills the typical Gelth might have. Being so silent, they’re going to be stealthy and they can evidently sense their environment and communicate with anyone who is psychic, but otherwise we don’t see them doing anything that’s indicative of what they get up to. Possibly not much, lacking bodies as they do.

Other than psychic communication, their only special power is the ability to possess corpses.

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5E - Gelth Zombie

Medium undead, neutral evil

Armour Class: 8 (natural)

Hit Points: 34 (4d8+16)

Speed: 20 ft.

STR 10 (+0)	DEX 6 (-2)	CON 18 (+4)
INT 10 (+0)	WIS 10 (+0)	CHA 6 (-2)

Damage Resistances: piercing, bludgeoning

Damage Immunities: poison

Condition Immunities: poisoned

Senses: Passive Perception 10

Actions:

Unarmed. Melee Weapon Attack: +2 to hit, reach 10 ft., one target. Hit: 1 bludgeoning damage.

Challenge: 1/8 (25 XP)

5E - Gelth

Medium elemental, neutral evil

Armour Class: 18 (partially insubstantial)

Hit Points: 26 (4d8+8)

Speed: fly 60 ft.

STR 1 (-4)	DEX 16 (+3)	CON 14 (+2)
INT 10 (+0)	WIS 10 (+0)	CHA 10 (+0)

Skills: Deception +2, Stealth +5

Damage Resistances: cold, poison, thunder

Damage Immunities: acid, bludgeoning, piercing, slashing

Damage Vulnerabilities: fire, lightning

Condition Immunities: grappled, paralysed, prone, restrained

Senses: Passive Perception 10

Actions:

Possession. As an action, a Gelth can possess a recently deceased corpse, creating a Gelth Zombie, which becomes active at the beginning of the next round. If the zombie falls to 0 hit points, the Gelth is released unharmed, but then becomes vulnerable to external attacks.

Challenge: 1/4 (50 XP)

BRP - Gelth Zombie

STR 3D6 (10-11)	CON 2D6+9 (16)	SIZ 2D6+6 (13)
INT 2D6+6 (13)	POW 3D6 (10-11)
DEX 2D6 (7)	CHA 2D6 (7)
Hit Points: 15	Move: 8
Base SR: 6	Damage Bonus: +1D4

Armour: None

Skills: Grapple 50%, Stealth 30%

Combat Skills: Brawling 50%, damage: 1D3+1D4

BRP - Gelth

STR 0	CON 2D6+9 (16)	SIZ 1D6+6 (9-10)
INT 2D6+6 (13)	POW 3D6 (10-11)
DEX 2D6+9 (16)	CHA 3D6 (10-11)
Hit Points: 13	Move: 15
Base SR: 7

Armour: None

Skills: Dodge 80%, Fly 70%, Persuade 50%

Possession: A Gelth can possess a recently deceased corpse, taking one round to enter and animate the body. This creates a Gelth Zombie, which becomes active at the beginning of the next round. If the zombie is destroyed, the Gelth is released unharmed, but then becomes vulnerable to external attacks.

GURPS - Gelth Zombie

ST 10	DX 6	IQ 10	HT 14
Thrust: 1d-2		Swing: 1d
Speed: 5		Move: 3

Advantages: Doesn’t Eat or Drink, Doesn’t Sleep, High Pain Threshold, Injury Tolerance (Unliving)

Disadvantages: Appearance (ugly), Bad Smell, Cannot Speak, Compulsive Behaviour, Unhealing

Skills: Brawling-10, Stealth-8, Wrestling-10

GURPS - Gelth

ST 0	DX 16	IQ 10	HT 14
Thrust: 0		Swing: 0
Speed: 7.5		Move: 7
Size: -2		HP: 10

Advantages: Body of Air, Doesn't Eat of Drink, Doesn't Sleep, Enhanced Move-1 (Air), Possession (parasitic, dead bodies only), Telecommunication

Skills: Acting-12, Persuade-12, Stealth-18

Savage Worlds - Gelth Zombie

Agility: d6	Smarts: d8	Spirit: d8
Strength: d8	Vigour: d10

Skills: Fighting d4, Stealth d6

Hindrances: Mute, Slow (major), Ugly

Special Abilities: Undead

Pace: 4                  Parry: 4                 Toughness: 7                      Size: 0

Savage Worlds - Gelth

Agility: d12	Smarts: d8	Spirit: d8
Strength: 1	Vigour: d10

Skills: Persuasion d6, Stealth d8

Edges: Dodge

Powers: Possession (can possess a recently deceased corpse, taking one round to enter and animate the body. This creates a Gelth Zombie, which becomes active at the beginning of the next round. If the zombie is destroyed, the Gelth is released unharmed, but then becomes vulnerable to external attacks.)

Special Abilities: Elemental, Flight, Gaseous Form

Pace: 8                  Parry: 2                Toughness: 6                      Size: -2

STA - Gelth Zombie

Control: 6	Fitness: 12	Presence: 7
Daring: 10	Insight: 8	Reason: 8
Command: 0	Security: 1	Science: 0
Conn: 0	Engineering: 0	Medicine: 0
Stress: 13	Resistance: 0

STA - Gelth

Control: 11	Fitness: 9	Presence: 10
Daring: 10	Insight: 8	Reason: 8
Command: 1	Security: 1	Science: 1
Conn: 0	Engineering: 0	Medicine: 0
Stress: 10	Resistance: 0

Gaseous: Cannot be injured by physical attacks; can enter a recently deceased body and possess it, creating a Gelth Zombie

DW Monsters: The Forest of Cheem

The second story of the modern show is The End of the World, which features quite a few different aliens. It’s difficult to say too much about many of them, however, either because they are represented only by a single individual (the Moxx of Balhoon), they aren’t really aliens (the Adherents), or both (the Face of Boe and Lady Cassandra). This leaves only the Crespallions, who don’t seem all that different from humans, and the Forest of Cheem.

The Forest have not appeared again in the TV series, but have returned in a couple of stories in the audio anthology Tales of New Earth (which reveals "Cheem" to be the name of a planet to which they were transplanted), and occasionally in the comics.

DW Monsters: The Nestene Consciousness

The first story of the modern series features the Autons, which I have already described. However, the story also features the creators of the Autons, the alien race known as the Nestene, and it is now time to look at those specifically.

One could argue that, strictly speaking, any Auton story is also a Nestene story. However, not all such stories include a direct appearance by a member of the race. In the TV series, we have only seen them directly twice, in Spearhead from Space and Rose, although they have perhaps been more common in the assorted spin-off media. But, for the most part, there is, as one might expect, considerable overlap and, unsurprisingly, there are no Nestene stories that don’t also feature Autons.

DW Monsters: Eight-Legs

The next story we come to is The Monster of Peladon, which, for the most part, features the same aliens and creatures we have already seen in The Curse of Peladon. There is one new alien race introduced, the Vegans (yes, that’s actually their name), but the one individual we see isn’t around long enough to tell us much about his wider race. The tie-in novel Legacy does add that the race can see in the infrared and adds some further detail about their culture, but they remain tangential enough in the TV series itself that I am going to leave them out. Which brings us to the final Third Doctor story, Planet of the Spiders.

DW Monsters: Exxilons

The first two stories of season 11 are:

• The Time Warrior – The first appearance of the Sontarans.

• Invasion of the Dinosaurs – Dinosaurs are real-world creatures and often already statted up in RPGs

The story that follows is Death to the Daleks, which has exactly the main foes that you would expect it to have. It does, however, also feature the Exxilons. While there’s no reason to suppose Exxilons are dramatically different from other humanoids, they can serve as an example of a primitive race and do at least have some minor differences from regular humans. They appeared only once in the TV series, but have appeared twice in audio stories and, because of their history as an advanced space-faring power, have occasionally been mentioned in tie-in novels and elsewhere.

Description and Biology

The Exxilons are hairless humanoids with rough skin, flat noses, and large eyes. Since they are alien and not even as visibly similar to humans as Time Lords are, we can’t conclude too much about their biology and internal anatomy. The humanoid shape has some implications for this – the presence of a rib cage implies that that is where the lungs are, for example – but there are limitations. One thing that might be worth noting is that we never see any evident females. This could be due to a patriarchal society that hides their women away, but it’s also possible that they just aren’t mammalian, and the sexes aren’t that easy for we humans to tell apart.

Another difference is the large, dark, eyes which fit with the idea that the Exxilons are naturally nocturnal (or subterranean, as stated in the novelisation). This, of course, does not imply anything like the magical ‘darkvision’ of D&D, but they should be able to see in much fainter light than humans can and be more affected by bright glare than we are.

Game Attributes

The living Exxilons that we see are all warriors and their society appears to be one of hunter-gatherers, so it may be that this is true of the bulk of their population. They seem to be reasonably well-built, as one would expect for someone trained as a warrior, but the average individual is unlikely to be remarkable by human standards. The harsh environment in which they live also implies a reasonable degree of physical fitness.

While they are primitive by the time period seen in the story, in the past they were a highly advanced spacefaring race. This indicates at least human-level intelligence and, although one could argue that their current ‘degenerate’ state has lowered this somewhat, it’s perhaps more likely that it remains the same as it always was. Their limitations are in their skill and knowledge, not their basic brainpower. 

Speaking of which, their skills are likely to be the same as any other hunter-gatherer. We know that they can use bows and other simple weapons are surely in their repertoire. Survival skills are also a must and they probably have abilities relating to hunting and the local vegetation (such as it is) even if there’s nothing in the TV story to indicate what their prey might be. Religion is central to their society, so that may be relevant, too, depending on the game system.

They don’t have any particularly exciting special abilities, but their skin looks tough and resilient, so there’s probably some minimal armour, equivalent to leather. And, of course, there’s the night vision.

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5E - Exxilon

Medium humanoid, neutral

Armour Class: 11 (natural)

Hit Points: 17 (3d8+3)

Speed: 30 ft.

STR 12 (+1)	DEX 10 (+0)	CON 12 (+1)
INT 10 (+0)	WIS 10 (+0)	CHA 8 (-1)

Skills: Athletics +3, Religion +2, Survival +2

Combat Skills: Ranged Attack +2, Melee Attack +3

Senses: Passive Perception 10, Night Vision (the Exxilon treats dim light as if it were bright light and regular nighttime darkness as if it were dim light, but cannot see in pitch blackness).

Challenge: ¼ (50 XP)

BRP - Exxilon

STR 3D6 (10-11)	CON 3D6+3 (13-14)	SIZ 2D6+6 (13)
INT 2D6+6 (13)	POW 3D6 (10-11)
DEX 3D6 (10-11)	CHA 2D6 (7)
Hit Points: 13	Move: 10
Base SR: 5	Damage Bonus: 0

Armour: 1-point leathery skin

Skills: Hide 40%

Combat Skills: Bow 50%, Brawl 50%

Night Vision: An Exxilon’s combat skills do not become Difficult in conditions of near-total darkness, but suffer the usual penalties in pitch-black darkness.

GURPS - Exxilon

ST 12	DX 10	IQ 10	HT 12
Thrust: 1d-1		Swing: 1d+2
Speed: 5.5		Move: 5

Advantages: Fit, Night Vision-4

Disadvantages: Fanaticism (worship the City)

Skills: Bow-12, Brawling-13, Climbing-12, Stealth-10, Survival (quarry-like planets)-13, Theology-9

Savage Worlds - Exxilon

Agility: d6	Smarts: d6	Spirit: d6
Strength: d8	Vigour: d8

Skills: Athletics d4, Fighting d8, Shooting d6, Survival d8

Hindrances: Vow (Minor, worship the City)

Special Abilities: Low Light Vision

Pace: 6                  Parry: 6               Toughness: 7 (1)                   Size: 0

STA - Exxilon

Control: 8	Fitness: 10	Presence: 8
Daring: 9	Insight: 8	Reason: 8
Command: 0	Security: 2	Science: 0
Conn: 0	Engineering: 0	Medicine: 0
Stress: 12	Resistance: 1

DW Monsters: Giant Maggots

Continuing through season 10, we get:

• Frontier in Space – While the Draconians are undeniably interesting, this is primarily due to their culture. In terms of basic attributes, they don’t seem that different from humans and can probably be described in the same way. Therefore, I will pass on them.

• I will also pass on the unnamed Ogron-eating blob monster from the same story, on the grounds we know almost nothing about it.

• Planet of the Daleks – It’s still not quite time for the Daleks on this blog yet…

Which brings us to The Green Death… and giant maggots!