Here's another Warriors story called Warriors: A New Dawn Book 1: A Prophecy Broken
Prologue:
"Come quick! Rock is dying!"
The soft darkness of the tunnel was disturbed by four pelts, one shimmering with starlight. An orange cat and a black cat with stars in her pelt knelt beside an old, hairless cat. Blood was seeping out of a gash on his neck. Suddenly, the dying cat turned to the watching cats.
"It is time." he whispered. "Time to reveal the truth."
"What now? We just survived the Great Storm." asked the black cat.
"You were never meant to do that. The warrior code
I left off in the middle of that sentence and never continued.
Rest of plot: I forget.