Lugh is hired to assassinate Dia by her father Count Viekone, who is an old friend of Lugh's father Cian. Cian asks Lugh to fulfill Count Viekone's request, saying he'll carry out the assassination instead if Lugh turns down the job.
and only the Tuatha Dé 
are capable of doing this.
ونحن توا دي هم الوحيدون
القادرون على ذلك
Und nur die Tuatha Dés
sind dazu imstande.
Y solo los Tuatha Dé seríamos
capaces de realizar tal hazaña.
Y solo los Tuatha Dé seríamos
capaces de realizar tal hazaña.
Qui plus est, nous sommes les seuls
capables de le faire.
E noi Tuatha Dé
siamo i soli a poterci riuscire.
e apenas os Tuatha Dé são
capazes de fazer isso.
И такое... будет по силам
только Туатха Де.