Doppelganger (starting race)

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Doppelgangers are a starting race added in SLASH'EM. Their primary trait is the ability to change form at will, much like monster dopplegangers. According to the SLASH'EM guidebook:

Doppelgangers have the enviable ability to change form at will, at a cost of some mystic energy (mana), although what they become may be a bit of a surprise, even for them.

Racial benefits and restrictions

Doppelgangers can polymorph into any permitted monster with the extended command #youpoly at the cost of 20 power - however, a given transformation may fail depending on how much more powerful the desired polyform is. They also gain an AC bonus for not wearing any body armor - this bonus is equal to their current level divided by four (with a minimum of 1), and stacks with other AC bonuses, e.g. from their role or dexterity.[1][2] They are still considered human for purposes of determining cannibalism and same-race sacrifice.

Doppelgangers' attribute caps combine the best of all other starting races, save for charisma: their strength caps at 18/**, while their charisma is capped at 15 (even lower than that of orcs), and the rest of their stats cap at 20. Low charisma is of little concern in practice - doppelgangers in need of charisma can simply polymorph into a foocubus or nymph, which set charisma to 18 and have relatively low base levels. More pertinently, doppelgangers are restricted in two-weapon combat as a tradeoff for their excellent stats and abilities, and reliance on polyself can potentially hamper attribute growth.

The following table outlines their base form's maximum attribute levels:

Strength Dexterity Constitution Intelligence Wisdom Charisma
Doppelganger 18/** 20 20 20 20 15

Intrinsics and techniques

In SLASH'EM, doppelgangers gain intrinsics and techniques at the following levels:[3][4]

In SlashTHEM, polymorph control is instead gained at experience level 25 - all other techniques and intrinsics remain unchanged.[5][6]


Doppelgangers can be either neutral or chaotic, and can be played as any role compatible with those alignments.


Main article: Polyself

For Doppelgangers, the #youpoly command can be used at any time as long as you have at least 20 energy and some nutrition to spare. If in your base form, you will be prompted for the type of monster you wish to polymorph into - if already polymorphed, you will return to doppelganger form without consuming any energy or nutrition. Successfully changing form uses up 20 energy plus an additional 5 energy points for each level of your new form - if you lack the energy for this, the excess is instead made up with nutrition points. A doppelganger that self-polymorphs will automatically remove and drop any body armor that would otherwise be destroyed in the process, unless they are cursed or beneath a cursed piece of armor.

The chance of being able to successfully polymorph into a given form is dependent on the difference between your experience level and the base level of the polyform - the higher the difference, the less likely you are to transform into that specific form, with the probability of failure calculated as follows:

\frac{\text{Monster level} - \text{Your level}}{5}

If you have polymorph control, you have eaten the corpse or tin of your chosen monster, or the above equation would yield a result of 0 or less, you have a 1920 chance of transforming successfully and a 120 chance that you "feel like a new doppelganger" and re-roll your stats.

Failure will instead transform you into a random monster or else cause you to re-roll your stats, and you will still remove and drop body armor as usual where applicable. Dopplegangers cannot polymorph into any restricted monsters, and attempting to do so (or else selecting a non-existent form) will prompt you to select another form up to five times.

You will remain in your polymorphed form for 500-999 turns, multiplied by your level divided by your new form's level - this is multiplied by 2 if you changed into a monster you have eaten. As with any other polymorph, you can remain in that form indefinitely by wearing an amulet of unchanging. While polymorphed, you gain that form's intrinsics and other properties - e.g., polymorphing into a strong monster sets your strength to 18/**, and polymorphing into a monster resistant to a status ailment you have (stoning, sliming, or illness) will cure that ailment. You still gain experience and levels as normal and can obtain intrinsics for your base form while polymorphed.

A polymorphed doppleganger passively restores HP for that polyform as any other monster would; however, while at maximum HP, your base form's HP will regenerate as normal instead, with the usual adjustments for regeneration and healthstones. Changed attributes are temporary, and any changes to those temporary attributes will be lost when you return to doppelganger form - you cannot exercise while polymorphed, and any exercise counter checks that occur after polymorphing only affect your temporary attributes rather than your base ones.

Feeling like a new doppelganger

Doppelgangers do not experience the typical effects of polymorphing into a new version of yourself - most critically, your level and hit points remain unchanged, preventing abuse and/or undue level loss.

When transforming into a "new" doppleganger, your current peak strength, dexterity, constitution and charisma are adjusted to within two points of their current value. If any changed attribute was previously below its peak, the new attribute will be adjusted in proportion to that peak - e.g., if your strength was 15 (max 16), and your peak strength went up to 18, your new strength would be 18 * 15/16. You also have a 110 chance of changing genders.

Extremely low hit points and energy are healed, and your nutrition is set to a random value between 500 and 999; sickness and stoning are cured, and the sliming process is not aborted, but instead reset to the beginning. You will always have a minimum of 10 HP and max HP after the polymorph, and your current and maximum power will have a minimum equal to your experience level.

Role-specific rules

Various roles have slightly different requirements for using the #youpoly command:

  • Starting from experience level 7, Doppelganger Flame Mages and Ice Mages that #youpoly will be prompted to "transform into your draconic form", which turns them into a red or white dragon respectively. This role's special ability overrides their previous polymorphing capability, which is often considered to be a bug.[7][8]
  • Doppelganger Lycanthropes need to have energy available in order to rehumanize, unlike other Doppelganger roles.
  • Doppelganger Undead Slayers are prevented from changing into an undead monster, which simply fails - additionally, if you actively attempt to do so while having polymorph control, you also take a -5 penalty to your alignment record and abuse wisdom.


The following forms are unavailable to all doppelgangers, with most of the restrictions and their exceptions being the same as in vanilla:


You will revet back to your base form once your polymorph timer expires, and you can also #youpoly at any time while polymorphed to revert back to your base form - you will retain as many hit points as you had prior to polymorphing, barring certain actions that alter your base form's HP (e.g, eating cursed royal jelly). When reverting back due to a polyform's timer expiring, the game rolls against your constitution - failing this roll causes you to lose half your base form's current HP.

If you die of hit point loss while polymorphed and you do not have unchanging, you will change back to your normal form and lose half your HP. However, if you die in any other way (e.g. stoning or being hit by a death ray), it will be permanent. If your polymorphed form was killed by a monster or explosion, you may also have a number of HP equal to your polymorphed form's level deducted from both your current and maximum HP. This penalty will be extracted every time if you have polymorph control, and 13 of the time if you do not.


The doppelgangers' high stats and useful ability to polymorph makes it an excellent choice for any role in either variant, since they often get the most out of that role's typical attribute distribution. Physical roles such as the Monk and Undead Slayer benefit greatly from the doppelgangers' high strength; magic-using roles such as Healers, Priests, Wizards, and Necromancers enjoy the high natural power and casting stats that the doppelganger offers, as well as the durability and better combat ability that can come with high physical stats.

However, the "jack of all trades" attribute maximums can also lead to doppelgangers suffering more from the lower attribute rolls - rerolling by transforming into a new doppelganger is a very limited "solution", and can result in even lower stats for those attributes. A skilled doppelganger will need to put their shapeshifting to use to compensate in these cases, and will also need to keep a close eye on their power, especially if casting regularly. Furthermore, a doppelganger must consider their defenses, e.g. employing a high-AC form with full armor coverage versus one with lesser armor, but a higher base AC augmented by racial and role bonuses.

Finally, survival will hinge on learning the ideal timings and scenarios for #youpoly. Over-reliance on polyforms is generally perilous: simply polymorphing to have an "extra life" can leave you thoroughly weakened if you are killed in that form, and failed polymorphs that reroll your stats or leave you in a much slower or weaker form in the midst of a fight can be deadly. As mentioned in the "Polyself" section above, constant polymorphing can and often will inhibit the exercise and growth of your actual attributes, in turn possibly resulting in much rougher late-game performance. Doppelgangers should select their polyforms carefully, and may need to make additional role-specific considerations - a doppelganger Warrior or Valkyrie might tend towards polyforms with high speed or hit dice to complement their strength, while Archeologists and other 'fragile' roles that are already fast may want a form that is durable, strong and/or capable of hindering foes. Certain forms can also be used to obtain various pets that can serve as aid in battles.

Good things to polymorph into

Before gaining polymorph control

  • Medium-sized humanoids can wear all armor and use weapons.
    • Hill orcs are guaranteed at level 2, and are strong monsters
    • Barrow wights are guaranteed at level 3, and can additionally drain levels.
    • Human mummies are inediate and normal speed, although not guaranteed until level 6. They make a good form if you want to wait around an altar and sacrifice. Human mummies have greater carrying capacity than their elven counterparts, and are available at the same level.
    • Salamanders (guaranteed at level 8) are humanoid with good AC and speed, and have 2 weapon attacks, a fire touch, and a fire crushing attack.
    • Doppelgangers can start polymorphing into mind flayers with a reasonable chance of success at level 6 or 7; the brain-eating attack will make short work of most monsters, but is useless against those without heads or brains, and downright dangerous against monsters with passive attacks. Mind flayers will not be stoned when attacking a cockatrice; the tentacle attack is instead turned off.
  • Demons have low natural AC, good attacks, and are a source of powerful pets through demon gating. The weaker demons become guaranteed polymorphable forms before a doppelganger gains intrinsic polymorph control at level 9 as well.
    • Spined devils have 18 speed (almost as fast as speed boots), are inediate, have resistances to fire, poison, and level-drain, have good natural AC, and hit fairly hard - this is a guaranteed form at level 5. It is strictly better either the elf or dwarf mummy, unless you are working with prayer (the spined devil is a major demon). They cannot wear suits, shirts or cloaks, but can wear other armor.
    • Chasmes can attack quickly and can repeatedly put foes to sleep. Great for killing shopkeepers (though this will come at the cost of -5 alignment record if you kill the shopkeeper without having him/her become angry with you due to not waking up).
    • Mariliths, guaranteed at 7, have normal speed, decent base AC, and attack 5 times. The multiple attack makes demon gating very effective.
  • Although not guaranteed until level 8, a level 5-7 character has a reasonable chance of polymorphing into a basilisk. They have the same passive attacks as cockatrices, though they are also larger and flagged as strong, making them much more capable of carrying a loaded inventory. As such, they can be very handy for traveling through dangerous early areas such as the Gnomish Mines. Nutrition can be a problem since you can't eat statues.
    • The similar and faster asphynx may look appealing, but it is very small and has no hands, so it can carry very few items and cannot pick any up at all.
    • If you're trapped by a single monster, chickatrices are guaranteed at 4 and will stone an attacking monster. However, they have extremely low base HP, can carry very little, and are slow, so they should only be used as an instakill in case of emergency.
  • Death dogs are guaranteed at level 2 and are fairly powerful. Their carry capacity is fairly limited though, so they're not good travel forms if you have a lot of things that you want to keep with you.
  • Unicorns are guaranteed at level 4. They have high speed and a decent attack, and can use #monster to remove some bad effects.
  • Mumakil are guaranteed at level 5. They have comparatively very strong attacks, but somewhat low speed. Especially good if you are fast or, better still, very fast.
  • Leocrottas are guaranteed at level 6. They are moderately fast and quite powerful, although unable to use any weapons or armor.
  • Oviparous monsters can provide some highly useful pets via egg laying, especially in the early game:
    • Gargoyles and winged gargoyles can sit and lay eggs that will hatch has gargoyles; normal gargoyles can wear armor, but the flying winged gargoyles cannot. Both forms also have excellent natural AC.
    • Rhaumbusun, guaranteed at level 2, are weak and slow but very effective at paralysing enemies which can help in scoring easy kills.
    • Soldier ants are guaranteed at level 3, and as pets, can if anything be almost too effective - they can often close in, kill and devour weak foes in the time taken for an unhasted player to make even a single move. Creating an army may be tempting, but this can lead to nutrition problems if you can't reach corpses in time. Spawning 2 or 3 is generally more than sufficient.

After gaining polymorph control

Main article: Polymorph control

Once you have obtained polymorph control, a world of powerful choices is open to you, including crystal golems, fire vampires, vorpal jabberwocks, and the nigh-invincible giant shoggoth.

See also