Does early and or other atheistic Buddhism mention Amida (or any other "other power").
Buddha speaks that the power of mära (mära bala) is something we should strive to win against though practice of Buddhism.
Buddha has also said that he doesn't see anybody else who exercises power as the mära does.
However mära also dies. Even Arhat Moghalläna has been mära.
Mära is also explained by Buddha as things that perish.
Our eyes, ears, nose, tongue, body and mind, when specifically considered as "me", "mine" or "my soul", is said by mära to be belonging to him when answering a question by Buddha.
The only time I can think of mention of an 'other power', is perhaps in Zen's Gateless Gate book of Koan's where there is mention in #42 of a girl next to the Buddha. I think that this "girl" may be Amida (who is neutre) but it is only a guess.
There is so the bull in Zen's ten pictures of the bull. It is a sort of pair to self and dissappears when enlightenment is achieved.