All bad endings are: Mouse, Cat, Dog, Fox, Wolf, Rabbit
Other bad endings: Chicken, Skunk, Demon
Wolf and Demon endings are missable if you play on the current public build, will change in full version.
The stone just decreases dmg taken not nullifies it. One and a half minute are probaly more than enough with just a bit of luck, you just need to find a key and the entrance into the ruin, afterwards there is no timer anymore