Merlin's Charm of Making

I’d like to make a remark about the Charm Merlin utters at the beginning of scene 2. According to Michael Everson, the enigmatic Charm of Making, which Morgana learns from Merlin, is evidently an invention, there being no known classical source. Transcribed phonetically as spoken in the film, the charm is pronounced:

[aˈnaːl naθˈrax, uːrθ vaːs beˈθud, doxˈjeːl ˈdjenveː]

The most likely interpretation of the spoken words, supposedly composed in Old Irish, though the pronunciation in the film has little relation to how the text would actually be pronounced in Irish, is:

Anál nathrach,
orth’ bháis’s bethad,
do chél dénmha

In modern English, this would be translated as:

Serpent's breath,
charm of death and life,
thy omen of making.

In Spanish, it could be translated as follows:
 
Aliento de serpiente
conjuro de la muerte y de la vida
tu presagio de creación.