>>96732940
Getting conductor and the ritual spell in your hand isn't the problem, the issue is that nephthys needs CaC-tier support on par with mitsurugi to be a real deck.
>ritual summon conductor
>summon devotee with her effect, then summon sacred phoenix with her effect
>link the two rituals into preserver, search cerulean and add back the ritual spell to hand
>ritual summon cerulean using sacred as the whole tribute
>???
Cerulean needs nephthys cards in hand to pop monsters (and only monsters), but even on a empty field, that's only 4200 damage. Linking both into promethean princess to then revive cerulean isn't enough either (5700), you need something else to OTK.

Diviner can sort of patch this up by searching a ritual monster/spell, then giving you an extra body if you use her as tribute, which means you'll have princess, sacred and cerulean on board, which is just enough damage (8100) to kill. But diviner won't always resolve, and you can't load up on non-engine because again, you need nephthys names in hand to pop monsters.
The deck is a complete mess.