Yeah the whole my religion/god is better than yours is sadly true even within the same religion’s sects.
https://forum.enlightenedstates.com/t/a-taste-of-vaikuntha-loka/17875/61?u=maoshan_wanderer
The deities are never in conflict, just the unrealized followers are 
My work is mostly associated with Hindu, Buddhist, and Daoist deities, but several Angelic, Egyptian, Greek, Afro-Caribbean, and long-forgotten unnamed deities have reached out and given me valuable guidance, which further enforces my belief that beings of light are at harmony with each other.
Also, rather than mantra A is powerful than mantra B, it is usually, practitioner A’s efforts are better than practitioner B. Usually, the power of any mantra lies in how successful one is in activating and perfecting it…