Attacks, some creatures and things can attack the clan this is what happens when they are not defeated.

Cats that have something that involves rocks taking control of them,  they will drop rocks in camp, possibly get some of the she-cat's pregnant if there are any toms, take prey, herbs, sticks, cats and they might kill some cats.

Rouges, they can take prey, herbs, sticks, cats, injure cats, kill cats, and get she-cat's pregnant if there are any toms.

Birds, they can take herbs and cats.

Petal and Flame, this event happens every 10 moons. Two rouges known as Petal and Flame will come to the clan. Flame has the chance to get she-cats pregnant while Petal tries her best to protect the she-cats.

Natural disasters, the most damaging one for the clan is an earthquake.

That's all that I can think of right now suggest more if you want to.