Something isnt adding up.. who IS the 1 star character??

So far we had all revealed characters ranging 2 stars up to 5 stars , but unless im mistaken there is NO confirmed 1 star character yet is there??
And no, it cant possibly be Dangai Ichigo or Mugetsu one, he's too OP to be 1 star (hardest to play as) right?

Could this mean theres still some other unrevealed character we dont know of? thoughts? something's odd.