Tensions between clans always ran high. Even when their entire sky came crashing down, as the cries of their lost loved ones filled the skies with cries of anguish and rage, no cat could trust another of a different home. Rain like tears fell from above, filling every empty hole. The rivers and streams gushed dark imminent death. Once caught there's no escape, its hold too strong.

The only way to avoid a watery demise in to climb closer and closer to the reach of claws made of burning light. Elders and kits struggled to claw their way up a wall made of mud. The cats who fell behind were swallowed by the angry waves never to raise their heads again. There was no time to grieve, the only way they had to go was up, up toward the skies that once held so much love.

Clanmates were torn from each other's sides as trees crashed and lightning flashed. Leaders abandoned their duties of keeping their clan safe and ran for themselves. When the storm finally eased after what felt like moons, many found themselves alone in a place they've never seen. Only a few managed to group together and even fewer with those of another clan.

(I made this up in a sitting, might revise later. This was made so you'd understand why water is literally everywhere and why the MCs hate each other)