Historically, there have been considered to be two types of possession - myst and ink.

These categories have come under scrutiny from academics in recent centuries, and this convention has ultimately been rejected.

Modern scholars define the types of saura - including possessions - as such:

• Standard saura
• Inky saura
  • Possessed ink
• Malformed saura
• Myst possession
  • Infestation
  • Frenzied

Standard saura is adequately summarized by the prior sections, and applies equally to lockettes and dexettes, with the caveat that dexette saura seems to exclusively originate from dextroluma souls.

Inky saura is no longer believed to be a possession at all, but to actually be a unique type of saura.  Some believe that inked lockettes actually stem from a unique species, similar to how dexettes come to be, but this is a fringe theory as there is no recorded contact with a species that seems likely to give rise to inky saura, and inky saura itself does not come with any unique traits that deviate from the baseline of a normal lockette.  It can be an inconvenient type of saura to have, compared to standard saura, as it is very heavy and can cause lockettes with it to move slowly.  In addition, it is easily lost by leaking through eyes, keyholes, and even the joints of those with BJD style shells, and so many lockettes with inky saura must replenish their saura more frequently.

Inky saura does have one unique feature with how it interacts with possessions, however - inky saura is capable of overtaking and transforming a myst possession.  Possessed ink takes the form of the myst possession and changes it to something tangible, made of the same ink as the saura.  If a myst possession took the form of three bees, for example, then those bees will become inky and tangible.  Possessed ink cannot survive its host, and will die with the lockette.  From what little is known, it cannot leave the lockette behind either.  Possessed ink may develop its own consciousness, and may help or harm their host according to their own desires.

Malformed saura is characterized most definitively by skeletal tails.  Other traits, such as tattered ears, broken charms and chains, or fragmentation beyond what is ordinarily possible to survive, are not always present on known malformed lockettes, but the skeletal tail is a giveaway.  These lockettes are unable to restore their saura by normal means.  Eating does nothing for them and the food must be physically removed from their shell before it can rot (if the lockette is in a sphere where decay is possible, of course).  Use of their summons only depletes their saura, rather than helping to regenerate it.  Sleep does nothing for them.  Instead, they must consume the life energy of others to survive.  Some like to call the malformed ‘vampires’ due to this.  Malformed seem to be best sustained by consuming the saura of other lockettes, but they can subsist by consuming the life of other creatures as well.

Myst possession, at its basic form, is an attachment to saura that takes a form similar to smoke or clouds.  Both magic and science alike have struggled to define what, exactly, myst is made of, but it is easier to study than saura, given that it is usually visible.  The most popular hypothesis is that it is a saura that has latched onto another saura as a parasite, but there is no proof of this.  The forms myst takes vary, but the most basic forms usually are cloudlike, smokelike, or shapes like wings.  Baseline myst possession has generally been recorded to have minimal effects on its hosts.  This is not to say it cannot cause the hosts harm, as there are accounts of baseline mysts causing lapses in memory or sabotaging the lockette host’s goals or actions.

Myst possession has two more powerful iterations: infested and frenzied.  These two types have been known to develop their own consciousness, with individual desires and agendas.  This is not universal.  Some instead manifest more akin to the concept of an ‘id’, acting based on impulses and habitual tendencies.

The infested subtype is quite easy to spot in most cases, as there will be additional eyes, either in the myst itself or placed upon the host’s shell.  Of the two myst subtypes, infested possessions are more liable to behave benignly towards the host.  While an infested possession can be harmful to the lockette for many reasons, it is most commonly if the lockette is for failing or denying the possession in some way.

The frenzied subtype, like the infested subtype, is typically quite easy to spot in most cases.  With a frenzied possession, there will be additional mouths, either in the myst itself or placed upon the host’s shell.  Of the two myst subtypes, frenzied possessions tend to be more dangerous towards the host as well as to others.  Many lockettes with frenzied possessions seem to be compelled to consume the saura or life energy of others, even when they have no need for it.  It is uncertain by what mechanic the possession can compel the host, but the hypothesis with the most support is that the mouths of a frenzied possession are capable of speech that only the host is able to hear.

Infested and frenzied possessions are capable of changing hosts.  While this is often done in the event the host is dying, it has been recorded to occur of the possession’s volition.  In most cases this transfer kills the host, but there are records of hosts who have managed to survive the process.  Infested and Frenzied possessions can be found on the same host at times - sometimes they seem to be part of the same possession, while at other times they appear to be in opposition.  As with most details about possession, the reasons for this are poorly understood.

Possession by nature is unpredictable, and experiences differ.  Some possessions never bother their hosts, and some hosts are able to resist or entirely ignore their possessions.  No analysis of possessions is truly capable of applying to every circumstance, as they are simply too varied.