The 2024 Monster Manual forDungeons & Dragonsbrought with it a lot of changes for existing creatures, and not just by extending their families or updating their moveset. Certain creatures have had their classification changed, and in most cases, the change is understandable, like werewolves now being monstrosities.
But one strange shift in creature type is for the gith, who are now considered aberrations. In case you are unaware, that is the same classification that beholders and mind flayers have, the latter being the sworn enemies of the gith. So why are these green-skinned people classified as the same as their slimy mortal enemies?

What Is An Aberration?
An aberration is a creaturefrom or heavily changed by the Far Realm, a place of tentacled madness outside the known multiverse. Barely peering into it can wrap the mind of even the bravest adventurers, andnot even the gods dare venture into its unknowable depths.
Spending even a single turn in the Far Realm can deal up to 9D6 psychic damage to a player.

While many creatureshold the classification of aberration, the ones that have spread the most throughout the multiverse arethe mind flayers. They come from a place beyond creation, trying tomake their Grand Design come to be; if that ever happened, it would markthe end of existenceas we know it.
Some aberrationsaren’t from the Far Realm at all, but they have features similar to those twisted creatures thatthey fall in the same category.One such example isthe slaadi, who hail fromthe chaotic plane of Limboand embody the disorder of their home realm.

Why Are Gith Classified As Aberrations?
In the 2024 Monster Manual, the two variants of gith - the githyanki and githzerai -are considered aberrations, even though they werealways classified as humanoidsin previous publications. This has most to do withtheir time spent as slaves of the mind flayers, and how eons of experimentation or merely living beside such creatures canfundamentally change someone’s nature.
The first to rebel against the mind flayers was known as Gith, hence why the entire species was later known as the gith.

This has always been represented bytheir different psychic abilities, something far from common among the humanoid species. However, it isn’t justtheir past that defines them, but alsotheir present, since their way of life is far from somethinganyone would consider common.
The githsplit into two clansdue to a shift in beliefs: the githyanki follow a path ofconquest and constant waragainst their former slavers, while the githzerai see that constant warmongering aspart of the Grand Design, wanting to take no part of it. While both clans areopenly hostile towards one another, the githzerai keep to themselves and build their settlements in places not frequented byeither the githyanki or the mind flayers.

The Githyanki
Thanks to Baldur’s Gate 3, many Dungeons & Dragons enthusiasts are aware ofhow the githyanki work, at least in general terms. They are highly militaristic, followingtheir lich queen Vlaakithin her quest against the Mind Flayers, although the place they call home isthe oddest part of their culture.
Githyanki means ‘followers of Gith.’
The githyanki live in the Astral Sea, a place that few visit and even fewer stay.Time doesn’t pass in the Astral Sea, so while that makes mortal races virtually immortal, it also means thatchildren don’t age, so they have to grow up elsewhere.
Githyanki are often met by denizens of the Mortal Planesthanks to their Creches, places where the eggs of their people are hatched, andthe young are trained.This allows the children to grow into maturity sothey can join their eldersin the Astral Plane.
The martial supremacy of the githyanki is enhanced thanks toan ancient alliancebetween Gith and Tiamat, where the githyankigained the service of innumerable red dragons. The true nature of the alliance is unknown, in particular, what exactly the dragon goddess Tiamat gainsfrom aiding the githyanki.
Therefore, the githyanki are aberrations due to:
The Githzerai
The githzerai arefar less militaristicbut no less serious, refusing Vlaakith’s rule andchoosing to live in Limboinstead of the Astral Sea. However, Limbo is no less strange for mortal creatures than the Astral Sea, being a placegoverned by thought, where structures can be built or collapsed by a mere whim.
Githzerai means ‘those who spurn Gith.’
While their biggest settlements are in Limbo, githzerai look forother chaotic planesto meditate on, such asthe Abyss or the Feywild. They aim tohone their mindsfor they suspect that the mind flayersstill exert some control over all gith kindand might one day come back to claim their slaves back into place.
Therefore, the githzerai are aberrations due to:
Are All Gith Aberrations?
What ultimately defines if a given creature is one type or the other iswhere their past generations have lived, and this is true not only for gith but alsofor all other species. An elf that is native to the Feywildwould be classified as a fey, while one from the material planewould be classified as humanoid.
Being an aberration alters certain game mechanics, particularly spells, so it is recommended that players always play as humanoids.
As such, a gith that haslived its life on the material plane, and experienced the same things a regular dwarf or orc might,would be considered a humanoid. Any gith that is part of the githzerai or githyanki, or thathas lived most of its life in similar circumstances, would beclassified as an aberration.