エルンマスの最初の3人の娘は、エリウ(Ériu)、バンバ(Banba)、フォドゥラ(Fódla)と呼ばれている。二人の名前は「アイルランド」の同義語で、それぞれアイルランドの最後の3人のトゥアハ・デ・ダナーンの王であるマック・グレイネ(Mac Gréine)、マック・クイル(Mac Cuill)、マック・ケシェト(Mac Cécht)と結婚していた。彼女達は土地と王権に関連しており、おそらく三重の君主の女神を表しているのだろう。次に、エルンマスの他の3人の娘が登場する。バドブ、マハ、そしてモリガンである。3人は裕福で、「狡猾の泉」、「激しい戦いの源」であると、歌詩で表現されている。モリグー(Morrígu)の名前はアナンド(Anand)とも言われている<ref name="LGE-62,64"/>。17世紀のジェフリー・キーティングの『アイルランド史』によれば、エリウ、バンバ、フォドラはそれぞれバドブ、マハ、モリガンを崇拝していた<ref>Geoffrey Keating, The History of Ireland |url=http://www.ucc.ie/celt/published/T100054/text021.html, Book 2 Section 11</ref>。
モリガンは「キャス・マグ・トレド」(「マグ・トゥレドの戦いの戦い」)にも登場する<ref>The Second Battle of Moytura, https://www.ucc.ie/celt/published/G300011/index.html, Corpus of Electronic Texts Edition</ref>。
The Morrígan also appears in the ''[[Cath Maige Tuired]]'' ("''The Battle of Magh Tuireadh''").<ref>{{cite web |title=The Second Battle of Moytura |url=https://www.ucc.ie/celt/published/G300011/index.html |website=Corpus of Electronic Texts Edition}}</ref> On [[Samhain]], she keeps a tryst with the [[Dagda]] before the battle against the [[Fomorians]]. When he meets her, she is washing herself, standing with one foot on either side of the river Unius, near [[Riverstown|Riverstown, Co. Sligo]]. In some sources, she is believed to have created the river. After they have sex, the Morrígan promises to summon the magicians of Ireland to cast spells on behalf of the Tuatha Dé, and to destroy Indech, the Fomorian king, taking from him "the blood of his heart and the kidneys of his valour." Later, we are told, she would bring two handfuls of his blood and deposit them in the same river (however, we are also told later in the text that Indech was killed by [[Ogma]]).
As battle is about to be joined, the Tuatha Dé leader, [[Lugh|Lug]], asks each what power they bring to the battle. The Morrígan's reply is difficult to interpret, but involves pursuing, destroying and subduing. When she comes to the battlefield, she chants a poem, and immediately the battle breaks and the Fomorians are driven into the sea. After the battle, she chants another poem celebrating the victory and prophesying the end of the world.<ref name="CMT166-CELT">{{cite book |url=http://www.ucc.ie/celt/published/G300010/text167.html |title=Cath Maige Tuired |chapter=The Second Battle of Mag Tuired |author=Unknown}}</ref><ref name="CMT167">{{cite book |first=Elizabeth A. (ed. & trans.) |last=Gray |url=http://www.ucc.ie/celt/published/T300010/index.html |title=Cath Maige Tuired: The Second Battle of Mag Tuired |section=167 |year=1982}}</ref>