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The Dullahan Minosaur is a Dullahan-themed Minosaur that was created by the Druidon Tribe from the negative emotions of Atsushi Miura, based on his self-centered belief that his failure to get married is not his own fault and is the main antagonist in episode 30 of the 2019 TV series called Kishiryu Sentai Ryusoulger.
The Dullahan Minosaur made its first appearance fighting Canalo, Towa and Bamba, but thanks to arrival of Melt, Koh and Asuna they joined in the fight to battle this Minosaur which wounds up the Dullahan Minosaur is gaining the advantage in this battle. However when Asuna mentions about "marriage" this caused the Dullahan Minosaur to used its special ability on the her making her to blind thanks to its host narcissism. Once that was done the Dullahan Minosaur retreats followed by Wizeru and Kureon.
A while later it appeared at the location where the druidon members chained it host to the chair, so that way when ever she explains to him the reason why he's not getting married this caused him to produce more negative emotion for the Dullahan Minosaur.
A while later it appeared battling Koh, Asuna and Melt also arrived to help the others fight against the Minosaur. Also thanks to Canalo to convince the Dullahan Minosaur's host to accept his fault the Dullahan Minosaur lost its power and ability making things much easier for the team to beat it. After that it was then destroyed by the arrival of Nada.