you have to become a Fire clan medicine cat or just press c+m then type deathberries, you'll get deathberries hidden in a fish, if they aren't hidden you can't kill anyone. and the wilted flowers can be found on the left of the Sunclan territory.
You can also wait for a gathering and then go into fire Clan to grab some deaf berries not every cat will fall for it so you kind of have to grab some fish by clicking on a lake and then click on the death berries this will make a trap
