Blue Slaad, Death Slaadi (The Lesser Masters), Green Slaad, Grey Slaadi (The Executioners), Red Slaad,
Ssendam - Lord of the Insane (Slaad Lord), Ygorl - Lord of Entropy (Slaad Lord).

The slaadi are great frog-like beings, who dwell on the outer plane of
Limbo where also dwell the githzerai (q.v.). Their form is of a large
bipedal frog, though some of the more powerful slaadi have polymorph
self and/or shape change abilities and will sometimes appear
as men (see the individual descriptions below). In frog form their
heads are huge and their claws extremely sharp and long.
The slaad hierarchy ascends from the comparatively weak red slaad to
the dreaded masters - creatures of unequalled ferocity and malignity.
All slaadi have names and may be summoned by a form of the cacodemon
spell (see ADVANCED DUNGEONS & DRAGONS
PLAYERS HANDBOOK) which will affect the red, blue and green <trim>
varieties as a demon type IV, V or VI. Slaadi masters have a 5%
chance of manifesting themselves if their name is spoken. If a master
does appear, it will immediately swallow the summoner and remove
him to Limbo.
Occasionally the slaadi will be found roaming the Prime Material Plane
on missions of woe.

All slaad speak a common slaad language - they are disdainful of the
languages of others. However, they all have a special form of telepathy
which allows them to understand and converse with any intelligent
creature. <added at DMG>

Slaadi Symbols: The symbols are magical symbols of rank in the form
of a jewel encased in the creature's skull beneath the skin of the forehead.
These are artificial devices which encase the slaad's life-force; they
may be removed by certain spells. On threat of destruction of the
gem, an intelligent being may force the monster to fulfil three
'requests', if they are within the beast's capacity. However, this can be
a very risky business since the slaad, when released and the gem replaced,
must be rewarded very well for its labour or it will turn on its
wouldhe controller and kill him. Rewards will usually comprise
human beings which the slaad takes back to Limbo as its slaves;very
rich treasure would, however, suffice.

The symbols have no intrinsic value - their value lies in the power of
the owner to control the slaad from which the symbol was taken. To
remove a symbol from a slaad, the following spells are effective:

Holy word, power word: stun or mind blank; any of these spells will
paralyse the slaad for 1-4 melee rounds and the symbol is caused
to emerge from the creature's forehead.

Limited wish: the caster may use a limited wish to 'wish' the symbol
from its position in the skull to the caster's hand; however, the
creature gets a saving throw against the spell, and if the die roll is
in the range of 01-65 the symbol will remain in place and the
slaad will immediately attack the caster berserkly.

Wish or trap the soul: as limited wish, but the creature has no saving
throw.

Alter reality: as limited wish, but the creature's saving throw is halved
(Le. the spell will succeed unless 01-32 is rolled).

Any slaad seeing a symbol being used by other than its slaad Owner
will react as does a slaad master to a summoning. Slaad symbols are
unique and readily identifiable by another slaad.


 

MP: The slaadi are apparently
natives, evolved or uplifted from the primal soup of chaos to their
present status as intelligent messengers of chaos. The Powers
who reside in the plane often make use of slaadi as messengers,
warriors, and servants (but the slaadi's chaotic tendencies often
cause missions to go astray). The slaadi are immune to the chaotic
effects of their own plane, though they can be affected by fire
and cold in the Prime Material. They are also affected by spells
cast in Limbo (a slaad can lounge in a pocket of flame that hangs
in the chaos of Limbo or pass through a pocket of melted earth or
magma, but it would be harmed by a [fireball] spell). Slaadi hierarchy
is as chaotic as the plane and usually extends only as far as
the more powerful  slaadi can reach. Slaadi and slaad lords are
found on all layers of the plane. They seem to prefer the native
chaos to those areas under the control of the Powers or githzerai.

Slaad are ruled by (or rather bullied, pushed, and cajoled by)
the slaad lords, of which two have been described in the FIEND
FOLIO tome: Ssendam and Ygorl. They are considered Lesser
Powers on their home plane and maintain relams that are stable
even in the absence of the lords. Ssendam's citadel is a golden
castle that rises from the edges of chaos itself, while Ygorl's
abode is a series of interlaced carved spheres that whirl through
the five layers. Ygorl is said to inhabit the innermost sphere.